Equipment Review: Aquarium Engineering ACR (Automatic Calcium Reactor)

[Dennis Cartier]

I decided to purge my ACR today and when starting back up, had some interesting results.

I disabled the CO2 using the switch I included on my auto tank switcher, purged out the CO2 until water was flowing out and then enabled the CO2 and open my effluent drain valve to allow displaced effluent to escape without back feeding. That is when I noticed that no CO2 appeared to be collecting in the ACR. The venturi was pulling 100% water and no bubbles were flowing through the media. The pressure transducer on my ACR controller was reading 7 PSI, which is a typical reading. I had the CO2 regulator set to 8 PSI, and the Clippard valve would always close before it ever reached 8 PSI in the past. To that point, after recently becoming aware of some ACR failures caused by over pressuring the reactor, I re-wired my controller to use the pressure transducer to keep the internal ACR pressure at or below 8 PSI by powering the Clippard valve from the programmable output on the transducer.

After not being able to get CO2 to flow, I relented and closed the feed pump ball valve and kept the effluent drain open. This allowed CO2 to start re-filling the gas pocket. As soon as I opened the feed pump ball valve, the CO2 re-filling halted again. What this showed me was that the Sicce pump I am tapping for the ACR feed, must have a head pressure of 7 PSI and was preventing the CO2 from pushing out effluent when the CO2 pressure was reading 7 PSI. The bypass valve on the feed for overriding the check valve was of no help in this case. Only closing the feed off entirely worked.

Then I increased my CO2 regulator to 10 PSI. The pressure transducer on my controller would climb to 8 PSI and then the over pressure protection would kick in and disable the valve. This allowed CO2 to again start to re-build the gas pocket even with the feed pump valve open and the effluent drain closed. This pattern continued of the valve being pulsed on briefly and then getting disabled, allowing CO2 to be added in tiny pulses.

After thinking about the new behaviour, I realized I no longer require the check valve bypass as the transducer is able to limit the overshoot above the feed pump head pressure. On the next purge I plan to see if the gas pocket can be rebuilt without using the effluent drain. It would take a few hours, but I am guessing it would work fine to slowly add CO2 as effluent is removed by my Masterflex pump.

I am the only person running this exact arrangement, Clippard valve with IFM pressure transducer, but nonetheless the results are quite cool.

Dennis

 

[PSU4ME]

What kind of co2 consumption are you guys seeing with these devices? I have a fairly low consumption tank and an 8” reactor so way overkill. I feel like it’s leaking somewhere. Thought these things are supposed to sip co2. I’m on my second 20# bottle in 3 months max

 

[Dennis Cartier]

If your tank is low consumption and you are going through a 20# bottle in 3 months, then I would agree, you probably have a leak. I believe some of the SPS heavy users were reporting 6 months, and I think that was for a 10# tank.

Have you tried spraying your fittings and tubing connections with water with a bit of dish soap in it?

I should add, I am still on my first 10# bottle, but I am like you, very low consumption, more for testing really. I have had the reactor running on the same 10# bottle since Oct 2020. I expect to take this tank offline before the end of the year, and doubt I will have reached the end of the bottle.

Dennis

 

[PSU4ME]

Hi Dennis,
I’ve sprayed the regulator and found an original leak (JG connection where the co2 line goes) but have since redone that. I feel it’s a slow leak there or in the control box which I haven’t sprayed. I wish that connection was the push on barb like in the carbon doser but they are the newest thing.

Always seems like it’s something……. 32 calls into Bill with no response either…… not a great feeling

 

[Dennis Cartier]

If you just fixed the slow leak at the regulator, then you will not know if that was the root cause for awhile.

I am opposite, I prefer the JG push style over barbs, but I try to only use the ones intended for pneumatics rather than the plumbing ones.

I would open the valve box and perhaps apply some soapy water by hand using a model sized paint brush to see if any of those connections are leaking. While you are there, look for any corrosion.

I occasionally run across leaks myself.

I adjusted the regulator on my backup tank down to where I thought 10 PSI should be, but my pressure transducer was still showing 11 PSI as the isolation valve will remain closed until it is made primary. I thought it would be stuck at 11 PSI (on transducer), but I just noticed the transducer has dropped to 10 PSI after a few days. So I might have a leak to hunt as well. I closed the valve on the backup tank and will see if the transducer drops below 10 PSI. If it does, there is a leak somewhere upstream of there.

Dennis

 

[PSU4ME]

Do you recommend a certain brand of fitting? I considered a diff regulator but they all seem the same.

 

[Dennis Cartier]

Do you recommend a certain brand of fitting? I considered a diff regulator but they all seem the same.

No recommendation on brand unfortunately. I use the ones from Princess Auto, which is the doppelganger of Harbor Freight in the US (or so Google says). They, Princess Auto, have a pneumatic section, so my thinking is the fittings they sell are intended for handling gases, and would better support CO2.

As for regulators, the major difference is the type of regulator. Single stage or dual stage. Single stage regulators regulate the tank pressure down to the preset pressure in a single pass, where dual stage use two steps to regulate the pressure down to your preset pressure. Dual stage regulators are known for being able to keep a stable output pressure right down to the end of a tank, where single stage can sometimes have stability issues as the tank pressure varies as it reaches it's end. The typical ones you see offered in the aquarium industry are all single stage.

The regulators I use are both Harris dual stage solid brass body regulators. I purchased the first one from a user on R2R that was switching to a Dastaco CalRx. So I purchased his Masterflex Digital pump, a Geo 618 CalRx, a Carbon Doser, an Apex pH probe / module, and the Harris regulator. It was a deal I could not pass up, lol. I have purchased several Masterflex pumps since then, but the one that came in that package remains the nicest one. I drive my ACR using that Masterflex, with the 618 as a secondary chamber and using the Harris regulator. I sold the Carbon Doser off as they are super simple to build and are based on the same Clippard valve I drive my ACR with, paired with a timer board. After reading all the posts with people raving about the Carbon Doser, I had a good chuckle upon looking inside it's case and seeing what it used.

Dennis

 

[Dennis Cartier]

I decided to purge my ACR today and when starting back up, had some interesting results.

I disabled the CO2 using the switch I included on my auto tank switcher, purged out the CO2 until water was flowing out and then enabled the CO2 and open my effluent drain valve to allow displaced effluent to escape without back feeding. That is when I noticed that no CO2 appeared to be collecting in the ACR. The venturi was pulling 100% water and no bubbles were flowing through the media. The pressure transducer on my ACR controller was reading 7 PSI, which is a typical reading. I had the CO2 regulator set to 8 PSI, and the Clippard valve would always close before it ever reached 8 PSI in the past. To that point, after recently becoming aware of some ACR failures caused by over pressuring the reactor, I re-wired my controller to use the pressure transducer to keep the internal ACR pressure at or below 8 PSI by powering the Clippard valve from the programmable output on the transducer.

After not being able to get CO2 to flow, I relented and closed the feed pump ball valve and kept the effluent drain open. This allowed CO2 to start re-filling the gas pocket. As soon as I opened the feed pump ball valve, the CO2 re-filling halted again. What this showed me was that the Sicce pump I am tapping for the ACR feed, must have a head pressure of 7 PSI and was preventing the CO2 from pushing out effluent when the CO2 pressure was reading 7 PSI. The bypass valve on the feed for overriding the check valve was of no help in this case. Only closing the feed off entirely worked.

Then I increased my CO2 regulator to 10 PSI. The pressure transducer on my controller would climb to 8 PSI and then the over pressure protection would kick in and disable the valve. This allowed CO2 to again start to re-build the gas pocket even with the feed pump valve open and the effluent drain closed. This pattern continued of the valve being pulsed on briefly and then getting disabled, allowing CO2 to be added in tiny pulses.

After thinking about the new behaviour, I realized I no longer require the check valve bypass as the transducer is able to limit the overshoot above the feed pump head pressure. On the next purge I plan to see if the gas pocket can be rebuilt without using the effluent drain. It would take a few hours, but I am guessing it would work fine to slowly add CO2 as effluent is removed by my Masterflex pump.

I am the only person running this exact arrangement, Clippard valve with IFM pressure transducer, but nonetheless the results are quite cool.

Dennis

During my latest purge/vent cycle, I have confirmed that using the pressure transducer's output to power the valve removes all the startup issues that could occur when having a check valve inline. I simply needed to disable the Clippard from opening, vent the CO2 in the reactor until water comes out, and then stop venting and re-enable the CO2/Clippard and allow the IFM transducer to re-fill the gas pocket slowly using the measured internal pressure to regulate it (by way of the IFM output).

This worked out very, very well. It took it a few hours to get to the point where the output stayed on 100% of the time rather than being toggled off after overshooting, but it all happened automatically.

This gave me an idea. This procedure can now be automated. Opening the CO2 bleed line for a set period of time should bleed off the gas pocket. During this process, the Clippard valve would need to be prevented from re-filling the gas pocket, so including a 24v relay in line with the float switch will stop this.

To open the CO2 bleed line, the pinch valve that the old controller used will make an OK test unit. I had my concerns with that pinch valve not closing correctly when I used it in the factory controller, but now that the IFM is limiting the gas pocket to 8 PSI max, I expect that it will be fine at that pressure.

So the automated venting procedure would look like:

1. Timer enables a 24V signal for the auto vent function to occur. This would be for a set number of minutes (E.g 1-3) and would be based on how long your ACR takes to push all the CO2 from the gas pocket. How long it takes depends on the head pressure of your pump, etc.
2. The 24V signal energizes a relay that is in line with the float switch, preventing the Clippard from being opened.
3. The 24V signal energizes the pinch valve starting the venting of the reactor.
4. After the gas has been vented, the 24V signal is removed and the pinch valve is closed and the relay is toggled back, enabling the CO2 once again. The reactor now slowly meters in the CO2 as effluent is removed by the peristaltic pump.

This would probably work using the factory controller as well. You would not be able to have a check valve in line with the feed though, so you would need to forego back feed protection, etc.

I have not made the change in wiring yet, but will at some point. Perhaps I will endeavour to put all the bits into a project box and cleanup the install at that point. I just thought I would post this tweak in the meantime.

Dennis

 

[Dennis Cartier]

After thinking about my idea for the auto venting feature, I decided to source a more elegant solution than just using the pinch valve from the factory controller.

When I vent manually, I close a ball valve on the CO2 re-circulation line to prevent the venturi from re-injecting the CO2 and slowing down the venting process by keeping CO2 spread out within the media. So having the capability of closing the re-circulation line during the auto venting process would also be beneficial. With that in mind, I have ordered a Neptune Research 3 way isolation valve from Ebay. The version I have ordered uses 1/8" NPT fittings, so I can use the normal JG push fittings. The Normally Open port will connect to the venturi feed, while the Normally Closed port will be used for venting and the input port connected to the CO2 port on the ACR. The valve is limited to 30 PSI max, but I have my max pressure inside the ACR regulated by the IFM pressure transducer I use, so that should not be an issue.

This way, when the 24V signal energizes and starts the venting process, the 3 way valve will close the venturi feed and start venting to waste. The same signal will toggle a 24V relay and break the circuit path for the float switch. I will be using an off the shelf electronic timer to power up the 24V PS, so the venting cycle will only be settable in 1 minute increments. I seem to remember the last manual venting took longer than a minute, so that should not be an obstacle. The preferred way is to stop venting just before or shortly after water appears in the venting stream. Currently I need to vent once a month to avoid weakening effluent, so venting 50% of the CO2 bubble once a week would probably still keep things working fine.

Hopefully the 3 way does not interfere with the ability of the venturi to draw enough CO2 in to keep things well saturated. I will not know that until I have the valves and have 1 installed.

Dennis

 

[Dennis Cartier]

UPDATE: Before considering construction of a v1, v2 or v3 controller, please see the post for the v4 controller which is a better option.

Equipment Review: Aquarium Engineering ACR (Automatic Calcium Reactor)

Disclaimer: This thread is intended to be an objective review of the features, performance, vulnerabilities, and experience of owning an Automatic Calcium Reactor by Aquarium Engineering. It is not a thread about the company, the owner, war stories, or what have you. Please join the conversation...

www.reef2reef.com

I have been working on a new version of my DIY controller that replaces the factory controller entirely and I am finally ready to share the details. This controller paired with an external peristaltic pump makes the ACR run much smoother than the factory one ever did and addresses all the former's short comings. The controller is easy to build (mostly just connecting of parts) and uses off the shelf industrial automation parts, intended for continuous duty.

Before I get into the controller, there are a couple of prerequisites that ever ACR owner should undertake.

Check Valve After Feed Pump

You should install a check valve after your feed pump and before the ACR. When the feed pump stops (for whatever reason, e.g. maintenance, power failure, etc.), the gas pocket in the ACR will drop in pressure to atmospheric and volume of the gas will expand displacing a fair bit of effluent back through the feed pump. The effluent will be at a very low PH and depending on the flow you are running at, the burst of effluent could spike your readings. Google "Boyle's Law" to see why this occurs.

My ACR did not include a check valve, and AE has stated it was not needed, however I have noticed some new parts are being shipped with the latest ACR's. I am not sure if any of these extra bits include an embedded check valve. If not, you should still add one.

Note: using the factory controller with a check valve has some caveats. I found that when restarting the ACR after a vent/purge, the presence of a check valve caused the factory controller to fail to equalize and sync up with the float switch level. This would cause the water level to drop below the float valve and potentially build up a gas pocket big enough to stop the circulation pump. The solution is to install a bypass valve that you can open for startup, and then close once the ACR is running stable.

Volute Reinforcement for Sicce Pump

If you do any work on the ACR that involves removing the Sicce pump, you will want to reinforce the volute before you put it back together. The wall on the volute is ridiculously thin and will crack just from screwing in the factory fitting. The o-ring on the fitting that provides for a nice water tight seal applies just a tad too much pressure and it is super easy to crack the volute. My suggestion is to reinforce the volute with a collar glued on to make it robust and not easily damaged.

Here is my solution to that. A piece of a CPVC fitting, sanded down and glued on. A 3D printed part would work even better.

Ok, now that those are out of the way, let's look at the replacement controller(s).

v1 Controller

Calling this version a controller at all, is a bit of a stretch. It is simply replacing the factory CO2 module with a Clippard valve and using the float switch in the ACR to energize the Clippard. This is exactly how the factory controller works (for CO2), the difference here is that I am using a robust industrial valve that is intended for continuous duty (unlike the factory parts). The valves are designed to operate for more a than a billion cycles before failure, can open an close in < 10ms and use a modest 19ma (at 24VDC). Keeping them energized 24x7 (as I do in my CO2 Tank Auto Switcher), results in a temperature barely above body temperature. They are also very, very quiet during operation. You will be hard pressed to hear it cycle over the sound of the circulation pump.

You will need the following parts:

https://www.clippard.com/part/ET-2-24-V
https://www.clippard.com/part/ET-C48

You will also need (2) 10-32 to 1/4" adapters for connecting to your CO2 tubing. You can source these online.

v1 ACR Controller (PDF)

I don't recommend building the v1 controller. The v2 and v3 have much better features and make the ACR run smoother. However if your factory controller gives up the ghost, then the v1 can be built quickly and step in easily for the factory controller (when paired with a peristaltic pump).

v2 Controller

This is the version of controller that I recommend for most ACR owners. The change from the v1 is the addition of a programmable pressure sensor, in this case an IFM Efector PN5204, and a vent switch.

The IFM sensor is what gives this version extra features. This part is a programmable pressure sensor that has a single output that we can control. We use the output to drive the Clippard valve through the float switch (and vent switch). This allows us to see exactly what is happening inside the ACR at all times. The pressure displayed on the IFM will match what the ACR internal CO2 gas pocket pressure is. As well, we can clamp the maximum allowed pressure to programmatically run the ACR at a different pressure than the CO2 regulator is providing. This is very handy to protect the ACR from an over pressure situation that can burst it's welds, and to mitigate issues that cheap CO2 regulators can cause (like end of tank dumping). Plus users are forever fiddling with CO2 regulators, and posting questions to the forum about them, and this makes all that away go away.

The IFM parts can be sourced from Ebay. This particular model (there are lots of models), is an obsolete part, no longer made, which works in our favour as they are easy to find cheaply. You should expect to pay about $30 for a used one in good condition. They were several hundred dollars new, and some vendor still try to charge a few hundred dollars for a use one, but don't pay more than $60 for one as there are lots around.

Operating instructions Pressure sensor PN52xx

In fact, you can buy a similar part, brand new for under $100. The ProSense QPSL-AP-42 from Automation direct is only $76 and provides similar features (a bit more features actually) and is new and still being made. The specs are here https://cdn.automationdirect.com/static/specs/prosensedigitalswtrans.pdf. They also provide direct replacements for the IFM's right down to the connector interface. They are $200 more than the cheaper version though.

For the IFM part, you will need a hookup cable:

M12 Sensor cable ifm efector EVC004

You will also need the Clippard valve, cables and connectors mentioned in the v1 controller version.

v2 ACR Controller (PDF)


The vent switch in this version is a feature I added that allows for easy manual venting of the ACR. That switch along with a 3-Way Ball Valve with John Guest 1/4" Push Connect from BRS, installed into the CO2 re-circulation line, provides a simple method of venting the ACR.

To do a manual vent procedure, you toggle the vent switch, this will prevent the IFM from driving the Clippard valve open, and then move the manual 3-way valve installed in the CO2 re-circulation to the opposite direction. This will stop the venturi from pulling CO2 from the gas pocket, allowing the circulating gas to collect there, and vent the gas pocket out through the 3-way valve. When the escaping gas turns to effluent, simply switch the 3-way back and toggle the vent switch. The IFM sensor will then take over slowly re-establishing the gas pocket. The time it takes to re-establish the gas pocket can be adjusted by the pressure limits configured.

The programming to use with the IFM is mode HNC (Hysteris - Normally Closed). I was using a set pressure of 8 PSI and a reset pressure of 7 PSI, but have recently switched to 9 and 8 PSI respectively. I can provide assistance when you get to the programming part (if needed).


v3 Controller

This is the latest version of the controller and adds automatic periodic venting as a feature. This required the addition of some more hardware and a slight bit more complexity (but still quite easy to DIY). I will show my building of the v3 controller at the end of this post.

To add the automatic venting feature, an electronic 3-way valve, a 24VDC relay and a 24VDC timer module was added. The electronic 3-way gets installed in the CO2 re-circulation line just like the manual 3-way from the v2. The 24VDC relay goes in place of the vent switch, and finally, the 24VDC timer module replaces the user involvement to make it automatic.

I used the following parts (find these locally):

GAEYAELE GR8 AC DC 12V 24V 48V Intermediate Relay Auxiliary Relay 8A 16A SPDT Relays (GR8-116,AC/DC 24V)
7-Day Heavy Duty THC 15A Digital Timer Programmable Timer Relay 16 On & Off Digital Timer Switch (24V)
NH / NEPTUNE RESEARCH 648T032 3-WAY ISOLATION SOLENOID VALVE 24 VDC 30PSI

For the 3-way (on Ebay), I recommend that model (648T032) for ease of use. They are hard to find used, and go for $165 new. So don't over pay for a used one. If you attempt to buy the one from the linked auction, the guy will accept $60.

v3 ACR Controller (PDF)


For my build of a v3 controller, I used the following parts. Most of these are optional and were used for neatness or ease of use.

Dinkle Combiner DK2.5N 10 Gang Power Distribution Dk2.5N 10 Gang Box Connector DIN Rail Terminal Blocks, 12-22 AWG, 20 Amp, 600V Solar Combiner, Beige
Dinkle DSS2.5N-02P DIN Rail Terminal Block Press-Fit Jumper (Pack of 50)
LMioEtool ABS Plastic Dustproof Waterproof IP65 Junction Box Hinged Shell Universal Electrical Project Enclosure Gray 5.9 x 5.9 x 3.5 inch (150 x 150 x 90mm)

Here are the collected parts that I used in the v3 build.

The box I chose had mounting points for a DIN rail and was sized to fit the rail included with the combiner package. I drilled some holes for the cable gland, power jack and the mounting holes for the Clippard and NR 3-way.

The DIN contacts and the rail they came on, fit nicely in the box. You can see that I have cross connected the 3 contacts on the left, giving 6 common contacts. The ground will connect to 1 and the other 5 will be drops for ground connections. The next 2 contacts are jumped, and will provide 3 drops for 24VDC. The next 2 contacts are again jumped and provide 2 drops (and 1 spare) of the 24VDC signal from the timer when it triggers. These drive the 24VDC relay and the NR 3-way valve. The next contact is used to connect the float switch to the Clippard (easier to see in latter pics with wires installed), and finally the last 2 will be unused spares.

The Clippard and NR 3-way valve are screwed to the top of the project box.

Here the wiring is underway. Note, I had to swap the cable gland out for a larger size as the mid sized one I started with ran out of space before I got the float switch cable inserted.

The wiring is complete here. I shifted the relay over and used the end plate to hold it in place as it was a bit loose on the rail.

Here it is installed on my ACR equipment stand, and in the process of being debugged (I had a couple of wires swapped).

Finally how it looks when complete. The IFM sensor is not shown, but is mounted at the top of the stand for easy viewing.

Of course I was super excited to test the automatic venting feature. It works as expected. I have been doing the manual venting procedure for months, so I already knew that it would work if automated. The only thing that I was not overly excited about was how long it took to re-establish the CO2 pocket after being vented. Until it is fully re-established, there would be no/limited bubbles rising in the reactor. I am not sure if having no bubbles circulating during that time affects the performance, but I like the presence of the bubbles as it looks more efficient.

I had worked out a plan that required adding a timed relay and a NC valve on the effluent drain to open the effluent for a few seconds after every vent cycle to allow the CO2 to rapidly rebuild the gas pocket, and then I decided to just try increasing the maximum allowed pressure on the IFM. I went from 8/7 PSI to 9/8 PSI and this noticeably sped up the rebuilding of the gas pocket. It turns out (I think), that the time it takes to rebuild the gas pocket is affected by the amount of pressure above the pump head pressure, that the IFM limits the ACR to. My pump's head pressure is about 5 PSI, adding 1 PSI to the headroom made a difference.

I have probably left a ton of stuff out. Feel free to contact me for assistance if you undertake to replace the factory controller.

Dennis

 

[Dennis Cartier]

After running the new controller for 24 hours, I have switched the set and reset points on the IFM back to 8 & 7. I found that the extra 1 PSI allowed the gas bubble to overshoot the float switch. The controller eventually recovered after all the CO2 was absorbed, but it took 12 hours of running at 2 PSI to do it. So I have moved back to the old settings as the internal pressure always hovered between 6 - 7 PSI when using those. I expect the higher pressure will allow the CO2 to absorb easier up to the saturation point.

While diagnosing what had occurred, I found that the internal pressure dropped way below what I had thought was my pump head pressure (5 PSI). As it turns out, the pressure floor appears to be 2 PSI, and I don't think it is the pump head pressure. I expect that it is the pressure the ACR sees from the small diameter RODI tubing it uses as a feed. This would also make sense as the relationship between the float valve, the incoming feed pressure and the CO2 feed pressure are all inter-related.

The 8 PSI I am using as the pressure ceiling appears to be the sweet spot. Though I chose it at random, when I received the reactor the factory was recommending 10 PSI, and I chose to use 8 as I thought it gave me some safety margin. Since then, AE also now recommends 8 PSI as the regulator pressure as well, so I guess I just got lucky with my first pick.

Dennis

 

[Dennis Cartier]

Ok gang, here are the numbers:

Oct 7th 52 dKh
Oct 19th 43.6 dKh
Nov 7th 39.6 dKh.
PURGE
Nov 10th 56.4 dKh

So the reactor saw a 29.8% increase in effluent strength following a purge. That is big.

That tells me that based on the numbers above, even with my EXTREMELY calm sump, I will have to purge at least twice a month to avoid a huge swing in effluent strength. So honestly I would just plan on purging if you have one of these, a simple solenoid hooked up to your apex would be an easy route, or, like I said I think AE has a purging controller out now/soon.

I am not sure which way I will go yet. I wonder if other saturation units like DaStaCo or Deltec have this issue too?

I tested my effluent today. It came in at 73 dKh. Which is what I was hoping it would be. I was trying to confirm a calcium test of the effluent that I did on the weekend. In that test my calcium was 920 ppm. So I thought I would test the effluent again for dKh and see if they matched up.

My tank's calcium level is 460 ppm and it's alk is 8.6 dKh. So 920 ppm - 460 ppm = 460 ppm / 20 = 23 * 2.8 = 64.4 + 8.6 = 73 dKh (2.8 dKh per 20 ppm ca)

I was pleasantly surprised when it worked out to pretty much dead on. When you have to dilute already small volumes, the opportunity for errors builds pretty quickly.

I am auto venting my ACR once a week, every Saturday morning at 9 AM. Dastaco units, and I assume Deltec, vent one or more times per day. My guess is that the harder you run the unit, the more often you need to vent. I am running a super low flow rate (1.3ml/min), so venting once a week for me is plenty.

 

[PSU4ME]

When you vent, is it just a quick open to let initial burst out or until water flows out?

 

[Dennis Cartier]

I have my ACR vent for 1 minute. Just gas and a bit of foam flows out. To vent all CO2, where water would eventually flow out, takes 1:20.

If you are doing a manual vent, then waiting for a stream of water to flow out would guarantee that you have vented all the CO2.

 

[panic]

This is awesome Dennis, thank you! I have my ACR vent every day at 3pm via Apex solenoid which I have found to be the time of greatest Alk consumption. I'm sure this time is different for everyone, but this is about 15 seconds longer than it takes to get a solid stream of effluent.

 

[RSnodgrass]

Was just on the FB group... looked like there were some changes afoot.
I'd been working on a mod for my ACR and this is what I came up with.

I will end up making the holes one size bigger though. *Patent pending.

 

[Dennis Cartier]

Was just on the FB group... looked like there were some changes afoot.
I'd been working on a mod for my ACR and this is what I came up with.

I will end up making the holes one size bigger though. *Patent pending.

Very clever, lol. When I first saw it I was puzzled what it was and what it was for. Now I see.

My ACR does not have any a bottom chamber, so I don't have any of these type of thumbscrews ... but I do in my Geo Kalk mixer. Great idea.

 

[Dennis Cartier]

Your comment on changes afoot got me to do something I never do, log on to Facebook. It looks like AE has a new controller in the works. This one has a peristaltic pump, good, the pinch valve in the previous models was a poor choice in my view. I do recognize the pump head, I ordered 10 of the stepper motor versions in from China a few years ago for a project, and I still have them.

I found the Chinese speed controller they are using on Ebay, it is for driving brushed motors, so the peristaltic pump they are using is not a stepper version. I am not sure that a brushed motor will hold up to the continuous duty required. I guess time will tell.

Hopefully AE has switched to a better valve for the CO2 in the new controller. The Clippard valves are not that expensive and would work so much better than the Chinese solenoid and pinch valves they have used up to this point.

I would love to hear feedback from anyone that gets a recent ACR that uses it.

 

[second_decimal]

I have to say, I am about to hook one of these (6” acr) things up and my expectation has been muted from I’m amped, this is going to be pretty neat to crossing my fingers I won’t be one of the problem cases to ***… I should have just bought something normal and used a ph probe / bubble counter. I mean, at the point I am going to have to build/rebuild components, add a ph probe what’s the point of an “automated” reactor?

 

[RobR]

Ok gang, here are the numbers:

Oct 7th 52 dKh
Oct 19th 43.6 dKh
Nov 7th 39.6 dKh.
PURGE
Nov 10th 56.4 dKh

So the reactor saw a 29.8% increase in effluent strength following a purge. That is big.

That tells me that based on the numbers above, even with my EXTREMELY calm sump, I will have to purge at least twice a month to avoid a huge swing in effluent strength. So honestly I would just plan on purging if you have one of these, a simple solenoid hooked up to your apex would be an easy route, or, like I said I think AE has a purging controller out now/soon.

I am not sure which way I will go yet. I wonder if other saturation units like DaStaCo or Deltec have this issue too?

I went from a ACR to Deltec TwinTech, big world of a difference! Should have went Deltec from the beginning. It is very quiet and no clanking noises from solenoid valves closing and opening. Biggest thing is that the TwinTech mixes the gas through the other chamber so it doesn’t churn through the recycling pump like ACR. Also it has auto purge built in. Numbers are stable coming from my Alkatronic.