The simplest (and cheapest) way of running a calcium reactor

[Ardeus]

I stayed away from saltwater tanks until 2006 because I thought that they were necessarily complicated. That changed when I saw a nano with just a clownfish, soft corals, live rock, a small powerhead, a heater and a T8 fixture.

The same thing kept me away from calcium reactors until recently.

All a calcium reactor does is melt media through the injection of CO2. I decided to simplify the process by eliminating 2 components:

- Dosing pump
- pH control.

Instead of the dosing pump I feed the calcium reactor through gravity, directly from the overflow.

Instead of checking the pH inside the reactor, I just measure alkalinity in the tank. That's it and it's been running like this for over 7 months now.



The whole setup to run a 200 gallon tank (calcium reactor and CO2 system) costed me less than 300 euros.

 

[joseserrano]

this will/can work, but you will/may run into inefficiency issues like this, due to not running a steady pump to feed/pull from the reactor. You can overly dose CO2 which brings with it a laundry list of potential problems.

 

[Ardeus]

It has happened because of the previous CO2 system being neither precise nor reliable. The Seneye alerted me immediately because there was a drop in the pH.

I also had problems with clogging the tube when I used a transparent airline. In a few weeks it would clog. The high unrestricted flow in the black tube solved it. In 3 months it goes from 300ml to about 200ml per minute and it doesn't seem to affect the output of the reactor. I have a piece of foam at the entrance of the tube inside the overflow.

My plans to complement the system is to get a kH monitor and a wifi power strip.

 

[joseserrano]

The KH monitor will help a lot if you then run you regulator off that. But you are kind of proving my point by saying the effluent drops from 300-200 in 3 months. You are theoretically using 50% more co2 for the same results when the line is clear. It is good you have the seneye to help you, but if someone is planning on setting this without some kinds of alert in place, it can be very harmful if they do not test frequently enough or do maintenance on the equipment and don't test to adjust. I do like that sponge you used as a profiler though, great idea.

 

[Ardeus]

I have tested changing the effluent between 300 and 200 ml and the KH in the tank stays stable (without any change in the CO2 rate). I was surprised and I think that the CO2 recirculation in the reactor may be responsible for this. When it gets close to 100ml, it becomes unstable.

Regarding the KH monitoring, I am waiting for the Seneye Coral. No pumps, no callibration, low cost... sounds great.

When you have a traditional calcium reactor setup, you have additional points of failure: the dosing pump and the pH control system. All can fail and create big problems in the tank, so they also need the same kind of vigillance I need with this setup.

 

[joseserrano]

All CA reactor work on the recirculating model (both CO2 and water), as mentioned in the first post, I believe your system can work, but was just trying to make those aware of possible issues. Nothing is fail proof. I am sure others will chime in and possibly explain what I was saying with better intelligibility

 

[Ardeus]

I agree with you and thanks for helping me to figure out the potencial problems and prepare for them.

The main problems I have seen come from:

- Unreliable CO2 system. I think I solved this with the Aqua Medic system.

- Clogging the tube from the overflow to the calcium reactor. The black RO tube with the sponge does the trick, I just need to clean it every 3 months.

- Breaking siphon. It never happened because there never was a power outage long enough for the syphon to suck all the water out of the overflow. I added the battery backup to the return pump so that this won't happen even if the power is out for several hours. If the power is out for longer than that, I will have bigger problems than breaking the shiphon of the calcium reactor.

- Changes in the alkalinity consumption of the tank, often caused by me messing with the corals. I have no way of detecting these changes at the moment other than the regular alk testing once per week. An alkalinity monitor will help with that.

- The wifi power strip will allow me to turn off the calcium reactor from anywhere if there's a problem (as long as there is power and internet access).

 

[jda]

The cost of any kind of automated dKh monitor will put the cost well above any CaRx that I run.

Mainline T to feed, used reactor, tunze regulator and a bottle is all that I use. Buy it all used if you can. Bottles from failed home brewers are usually cheap. It just runs 24/7 and is super reliable.

There is nothing really to fail here... all of these components are more reliable than a pH probe or a dKh monitor (for now, time will tell on these). The stuff that I choose are easily a decade reliable.

I have started to use a pre-filter before the CaRx. I never got many clogs before with the mainline T, but stuff does accumulate in there, so it is doing something.

 

[Ardeus]

The cost of any kind of automated dKh monitor will put the cost well above any CaRx that I run.

Mainline T to feed, used reactor, tunze regulator and a bottle is all that I use. Buy it all used if you can. Bottles from failed home brewers are usually cheap. It just runs 24/7 and is super reliable.

There is nothing really to fail here... all of these components are more reliable than a pH probe or a dKh monitor (for now, time will tell on these). The stuff that I choose are easily a decade reliable.

I have started to use a pre-filter before the CaRx. I never got many clogs before with the mainline T, but stuff does accumulate in there, so it is doing something.

If I understood correctly, you feed the calcium reactor from your return pump? What's your effluent rate and how do you keep it stable?

Regarding the alk monitor, I read that Seneye Coral will cost close to 200 USD (plus monthly slides).

 

[jda]

Flow control pinch on the outlet side. They are like 2-3 dollars, or something like that.

 

[C. Eymann]

I have siphon fed a reactor before on its own line from the overflow box, I used a pinch valve like JDA described.

I worked well for quite a long time, but because I was also using a reeffanatic reg/valve for CO2 control, it wasn't "set it and forget it", it needed adjustments every few weeks.

After I got a swagelok valve for CO2 and a masterflex for effluent, I went 8mo without touching it, last AlK test log was 9DKh, 8months later it was 8.5DKh, no fiddling whatsoever.

It was then that I decided I would never own/run a reef aquarium without a reactor.

 

[X-37B]

I run a tunze 7131 carx. The intake is pinched like your outlet. Swagelok co2 needle valve no ph controller. Simple and steady. Been running 2 months. Alk 8-8.2. Co2 easy to control. I may replace the screw pinch unit with the one in the pic. It looks better than the screw method tunze employes. I did have the tube bunch up against one side for a few days until I found it. The effluent kept going down. The design is very basic and the one above looks better.
Coralline growth is huge and all coral growth is excellerating.
In 2 months I have already noticed the level of carbonate in the reactor is going down.
This in my opinion is the simplest way to dose alk/ cal.

 

[Airw0lf75]

I’ve been using this very setup since 2003. It will work just fine. I can also mention, on my old Koralin unit, that even in a lengthy power outrage, the siphon will restart itself automatically because the recirculating pump will also turn back on and this produces enough movement to restart the siphon.

 

[waterskiguy]

I just started using a calcium reactor and o my have the time studying to figure out what I wanted to run and what o didn’t want to run. I went with a dosing pump, reactor and carbon doser hooked up to my apex. For me, it simplifies things if I have a steady heartbeat to work with, just being able to adjust parameters when and where I need. To me this more complicated way of doing it is much more simple. When you say “simplify” things, I’m guessing you mean to have fewer components, not simplifying the tuning and stability of the reactor. The way you’re mentioning has been done for years with success and I don’t see anything wrong with it. I would take a guess that maybe a line off of the return would be more steady than an overflow. I guess this may create a problem if the return pump were to run the backup battery out and the chamber would get over saturated with co2 then dumped it back into your tank when the return pump came back on. The PH would drop and really hurt your tank. This is kind of why I like having control over PH. Two ph probes would have to fail, at the same time, in my system and start reading way higher than their range for mine to skip a beat. Even if that happened, the apex would warn me and shut the reactor off before anything bad happened. Several different layers of redundancy would have to fail for it to have any ill affect on my tank.

I commend you for being able to keep yours stable without the use of any kind of controller or stable source. I’d say keep it going like it is if it’s working for you. You know the penalty for failure.

 

[Ardeus]

I just started using a calcium reactor and o my have the time studying to figure out what I wanted to run and what o didn’t want to run. I went with a dosing pump, reactor and carbon doser hooked up to my apex. For me, it simplifies things if I have a steady heartbeat to work with, just being able to adjust parameters when and where I need. To me this more complicated way of doing it is much more simple. When you say “simplify” things, I’m guessing you mean to have fewer components, not simplifying the tuning and stability of the reactor. The way you’re mentioning has been done for years with success and I don’t see anything wrong with it. I would take a guess that maybe a line off of the return would be more steady than an overflow. I guess this may create a problem if the return pump were to run the backup battery out and the chamber would get over saturated with co2 then dumped it back into your tank when the return pump came back on. The PH would drop and really hurt your tank. This is kind of why I like having control over PH. Two ph probes would have to fail, at the same time, in my system and start reading way higher than their range for mine to skip a beat. Even if that happened, the apex would warn me and shut the reactor off before anything bad happened. Several different layers of redundancy would have to fail for it to have any ill affect on my tank.

I commend you for being able to keep yours stable without the use of any kind of controller or stable source. I’d say keep it going like it is if it’s working for you. You know the penalty for failure.

The 1st CO2 system I got not only was very difficult to regulate to the amount of bubbles per minute, but it was also unstable.

One day I received an alarm from Seneye telling me the pH in the tank was too low. I immediately suspected that the problem was with the calcium reactor and I was able to correct it in time. I just ordered a wifi power strip so I can do this when I'm away from home.

I didn't know that there were more people running their calcium reactors like this, because during the time I researched it, I couldn't find any mention of using gravity to feed the reactor or not controlling the pH in the reactor.

I thought about using a line from the return pump to feed the reactor and I may try it. If the power fails, the return keeps running on the battery, but the the CO2 will shut off, so no risk there. Feeding the reactor through gravity just seemed simpler.

Seneye is still working on their alk monitoring system (Seneye Coral) and I suggested they created a smart power socket that would turn off if the alk value reached the level you want. You could plug the CO2 system there or even a dosing pump, for people using 2 part.

This would not only help in preventing accidents with the CO2 supply, but it would also help in reducing alk variation throughout the day and prevent alk spikes when the alk consumption of the tank drops for whatever reason.

The Seneye normally gives you 48 readings per day so this could be much more effective than the current alk monitoring solutions at a small fraction of the cost.