Aquarium Engineering-ACR Calcium Reactor

[gdemos]

Ok, I have watched the video. You can't, or should not, do a passive feed from the sump. The reason you are seeing an air gap build when you switch from a manifold feed, with a Masterflex metering the flow out of the effluent line, is that the CO2 pocket will build up to the pressure that you are feeding from your regulator (hopefully 8 PSI), and once you remove the head pressure from your feed pump, the CO2 pocket will expand back to atmospheric, back feeding effluent into the sump.

I have some questions of my own. You appear to have a pH probe mounted in your ACR? You also don't have anything plugged into the float switch, so you are not running it in automatic mode? I know you said your controller died. How about we build a new one for you that will work better than the factory?

Have you seen the other ACR thread with my DIY replacement controller?

Equipment Review: Aquarium Engineering ACR (Automatic Calcium Reactor)

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...

www.reef2reef.com

Even though the factory died, you can still use the ACR in automatic mode with a few parts. I would be happy to help you do that.

Hey Dennis. well the back story on the Controller is it died twice. First time i noticed leaking at the controller, Bill sent me a new box. I belive this melted down my 10+year old acro system. essentially it lead to contaminated effluent and the rapid drainage of my Co2 tank and subsequent alk spikes.

the second time was just recently with the new control box, i caught it just in time and decided to tap/thread for a pH probe and go with the masterflex.

thats correct, nothing plugged to the float switch because the control boxes are toast.

i'd like to hear more about your fix and will look at your thread... meanwhile what can i do?
will a slight feed from manifold be okay or will this build up excess pressure and volume?

will pushing as opposed to pulling with masterflex help or yield same result of air pocket?

i have confidence in masterflex / pH probe / carbon doser regulator... so i'm okay with my non automatic approach, but not okay with this air pocket obviously

 

[Dennis Cartier]

The air gap is CO2 expanding back to atmospheric. As the pressure drops, the CO2 expands inverse to the pressure. So if you have 8 PSI of CO2 in the pocket, and you pull fast enough to drop the pressure to 4 PSI, the volume it occupies doubles. So dropping back to atmospheric will give 8 x the volume.

Ok, running it using a PH probe will work, but your effluent strength is going to be lower, hence your Masterflex will have to run faster and pull more effluent. I would probably switch the Masterflex to the feed side and push through the ACR if you are using it in this style (pH). Without the benefit of the float switch, you can't really run the ACR above atmospheric. You just need to move the Masterflex to the feed line and leave your effluent dripping into your sump.

Have a look at the other thread. Replacement controllers are not too hard to build and work great.

 

[gdemos]

Mcgyver I am not... i checked out your thread quickly enough to realize i'd need to read it several more times before i contemplated that route. i've learned that somethings are above my paygrade

okay, so i'm gonna feed via masterflex and see how it goes... the masterflex i'm running now can go up to 500+ ml/min. i understand the effluent will be less potent (i used to run ACR at approx 45 dkh effluent at 1/135 on off).

 

[Dennis Cartier]

I am not sure what your demand is, but you should be able to get about 1/2 the dkh by running pH based. So I doubt you will need 500 ml a minute. If you do need 500 ml a minute, I am envious, lol.

 

[Dennis Cartier]

I have not ran the factory controller in along time, but 1/135 would be about 5 ml a minute (just a guess). It would depend on the head pressure of your feed pump.

So plenty of headroom

 

[gdemos]

Yea will have to see what the effluent potency is.
Now that im pushing vs pulling w masterflex i know this question has been debated…why would pushing be advantageous?

I see advantage of pulling: (a) if CaRx had leak or leak in tubing at masterflex etc then there would be no flood, i am only able to lose as much water as the reactor vessel depth of effluent outtake

why would pushing help with the air bubble at lid problem? If the air bubble at lid problem is due to atmospheric pressure balance how does pushing solve this?

 

[Dennis Cartier]

Yea will have to see what the effluent potency is.
Now that im pushing vs pulling w masterflex i know this question has been debated…why would pushing be advantageous?

I see advantage of pulling: (a) if CaRx had leak or leak in tubing at masterflex etc then there would be no flood, i am only able to lose as much water as the reactor vessel depth of effluent outtake

why would pushing help with the air bubble at lid problem? If the air bubble at lid problem is due to atmospheric pressure balance how does pushing solve this?

The difference is that you will not be running above atmospheric as the effluent line is open. In theory, you could pull with the feed line in the sump, but I suspect the recirculation pocket is messing you up. Pushing should work for sure though.

When running in auto mode, then the opposite is true, pulling is the only mode to use as you want to run above atmospheric.

 

[gdemos]

Well... That didn't work...
feeding from masterflex after about 2 hours i went and checked, the air a top of ACR was so much that pump ran dry.

So, I've got no choice but to go back to a feed from manifold and a pull of effluent from lid to Masterflex. This does build pressure in reactor even with manifold on a slight feed. If i pull the recirc line there's a swift blast of pressure. and of course, if i pull the effluent, theres a swift blast of water (that woke me up).

Why did the Masterflex push fail?
What will happen if i keep the manifold feed PLUS the masterflex pull?
Do i have to somehow strike a balance of the feed volume/pressure to meet the masterflex pull rate?
Will too little volume/pressure from the manifold feed cause the same problem?
What kind of pressure can this vessel handle?
Why is this so difficult?

 

[gdemos]

i suspect the first thing to fail will be the return pump volute?

 

[gdemos]

To add insult to injury Just in the course of experiments here where there have been occasional dumps of effluent to the sump I already had alk spikes! From 9 to 10.9

this is not going well!

so I unplugged co2 solenoid to avoid further disaster.
I am concerned about excess pressure in this reactor. Am I going to blow off the lid/ the push fittings/ the pH probe holder/ the recirc pump volute?

 

[gdemos]

To add insult to injury Just in the course of experiments here where there have been occasional dumps of effluent to the sump I already had alk spikes! From 9 to 10.9

this is not going well!

so I unplugged co2 solenoid to avoid further disaster.
I am concerned about excess pressure in this reactor. Am I going to blow off the lid/ the push fittings/ the pH probe holder/ the recirc pump volute?

 

[Dennis Cartier]

Ok, how are you metering the CO2? Just the carbon doser? The only way you can get build up beyond the intake is if your CO2 input is more than can dissolve in the reactor. Are you using the pH probe for metering? If so what is the pH reading?

You will not over pressurize the reactor with an effluent open to the atmosphere. There have been cases where ACR's failed from being over pressurized, but that involved regulators set much higher than the recommended 8 PSI.

The volute is fine, but it is fragile when removing or screwing the fitting into it. I broke a couple that way, lol.

The effluent dump is concerning. As an SPS guy I feel your concern.

 

[gdemos]

Hey Dennis thanks for helping…and your understanding!

i am metering co2 by phProbe w/carbon doser regulator and apex. Co2 On above 6.8, co2 Off below 6.40

 

[gdemos]

And now that im back to pulling with masterflex the effluent is Not to the atmosphere… it is to the masterflex

pushing by masterflex without manifold assist failed: after just an hour or so the air gap in lid ran the pump dry!

pulling with masterflex and passive line in sump(no manifold feed) failed…air gap at lid ran ph probe dry amd eventually would run pmp dry

so i reverted to manifold feed and pulling effluent from lid with masterflex

im out of options

 

[Dennis Cartier]

What is your bubble rate set to in the carbon doser? Pretty sure we need to slow it down a fair bit. It is putting CO2 in faster than it can dissolve or register a lower pH. Is the pH probe calibrated and accurate. Just throwing out all the possible causes for your issues.

No worries on helping. I am in an emergency room waiting area, so it gives me something to do that doesn't involve focusing on how long I have waited, lol.

 

[gdemos]

Should i go back to push w masterflex, slow gas down further, and effluent to atmosphere? At this point i can afford to go without co2 for. Few days given the blasted alk spike

 

[Dennis Cartier]

Yes, go back to push and slow gas down to a bubble every x seconds. Not sure what x is, probably about 1/2 to 1/4 of what you have now.

Thinking about how to get you back running more reliably, I have a way to get your ACR back to running automatic, using your carbon doser and a male and female power adapter. We can tackle that once we get you stable .

 

[Dennis Cartier]

Your CO2 is not being reigned in by your Apex/pH probe currently. So slowing the bubble rate down, you should be able to find a sweet spot where it just bubbles constantly at a slow rate and keeps your ACR effluent up enough, but not so much as to build up a too large gas pocket.

I would turn it way down and work your way back up as you need stronger effluent.

 

[gdemos]

Should i go back to push w masterflex, slow gas down further, and effluent to atmosphere? At this point i can afford to go without co2 for. Few days given the blasted alk spike

Ive got carbon doser set with low pressure gauge at 8 and black dial at 6 seconds per bubble

 

[gdemos]

Ive got carbon doser set with low pressure gauge at 8 and black dial at 6 seconds per bubble

So as I understand the carbon doser the “seconds per bubble” black dial… the higher the dial (goes from 0.1 to 10) 10 sec per bubble gives me a larger bubble with less frequency. A lower number say 1 sec per bubble gives me smaller bubbles more frequently. In my case, i want to slow gas down, whats better 10 sec per bubble or 1 sec per bubble?