Calcium Reactor tuning, too much CO2, right level for the tank though

[Ocelaris]

I have a Korallin C1502 on my well stocked 3 year old SPS heavy 250 gallon tank, and it works great, except I'm collecting excess CO2 (or air, but I believe CO2). I do use pH as a reference, but but I don't use that for the regulator, I go by my tanks demand. If I am at 8.2 dkH, and ph in the reactor is at 6.7 at 32ml/min, my alk in the tank stays stable. I use the bubbles per second, usually one per 2-3 seconds as a reference which correlates well to the pH probe. But over the course of the day I collect CO2. So my question is, how do I use less CO2, that is absorbed by the admittedly small reactor. If I lower my bubble count it lowers the pH in the reactor and hence my tank's alkalinity drops. Lower flow?

I've read JDA's how to tune with alkalinity, and I believe in theory I'm abiding by the principles, measure output, which is determined by bubble/pH, don't use the dump and store (which I'm not).

I'm refilling the chamber every few weeks, as I find if the chamber isn't right near the intake it seems to collect more CO2 than if it is lower down. I also am using the newer reborn media, which has a fair amount of shells, which I think tend to collect and clog up the flow. Once I change out the media completely it is pretty resilient, but after a month or two I'm back in the same position with collecting a lot of CO2 at the top. Is it just time for a bigger reactor? Thanks

Any help?

 

[Ocelaris]

So the Korralin C1502 was set up way back before constant duty peristaltic pumps were a thing, and looking at the comment Geo had about his older reactors building up CO2, I'm wondering if I'm facing something of a similar issue. On the other hand BRS says to "pull" instead of push with a peristaltic pump... I had thought the pump was maybe going bad, it's an eheim 1048, probably the original, over a decade old; but it moves water through the reactor fine. I even bought ARM large media to replace the pretty fine grained Reborn media. I haven't gone through any major changes, but I'm looking for advice if I can just tune the reactor flow/CO2, or I'm facing something more structural as my tank demands grow. Thanks





geo said:
For those that have a build up of CO2 in there reactors please read:

If you own a GEO calcium reactor that was built before 2009 (manifold connected to the lid via union) then this design was built to have pressure inside the reactor. Pressure was supplied to the reactor via small feed pump placed in your sump (MaxiJet/Colbalt 600 or Sicce 0.5) and the effluent control via micro ball/needle valve. These models went into production approximately in 1999 BEFORE continuous duty peristaltic pumps were being used in the aquarium trade. If you try to run a peristaltic pump ALONE on these models you will get a build up of CO2 since there is no pressure to compress the intoduced Co2 into the water column. Some users can get them to work normally if a high effluent rate and low Co2 dosing is used. The work around if you must use a peristaltic pump with these models, although we do not recommend this, is to use both a small feed pump (<125 gph) *****WARNING connections must be secure and O-Rings/Uni-seal in good condition******* and a peristaltic pump in the pull configuration. Yes the feed pump will be pushing against the peristaltic pump but at low enough pressure not to damage it. REMEMBER THIS IS AT YOUR RISK AND AGAIN THIS IS A WORK AROUND AND NOT RECOMMENDED BY GEO'S REEF. We do however recommend that you follow the original directions listed on our website with use of only a small feed pump. This pre-2019 design is proven for almost 20 years without any major issues. Our advice is to just use the feed pump. If you choose to use the equipment in a way that it was not designed it is at your own risk.

All GEO calcium reactors built since 2019 (manifold from side) are design to be used with only ONE of the following:
* A continuous duty peristaltic pump in the PULL configuration.
OR
* A small feed pump (<125 gph) such as a Sicce 0.5, MaxiJet/Colbalt 600.

Thank you and I hope this helps.
GEO

 

[outhouse]

Best move I made was a jabeo 1000 set it to run on 2nd setting from bottom, which is much better then that 1048. I use a GEO and with 320 G volume at one point I was running 1 bubble a sec and never had issues with co2 up top. I just use a trickle. Basically as low a flow as you can get without it plugging up. Second best addition was a huge second chamber to help raise PH. Another trick that helped was a long time ago I quit buying expensive media. Now I buy cheap finer coral gravel for DSB. With finer media your getting better coverage and it last longer. Last trick is try to get your gas shop to give you the largest bottle possible. even a 15g is way to small, I want a full size. refilling is same cost regardless of size.

 

[outhouse]

The maxijet feed pump is bulletproof. Still on my original one which has to be way over a decade old.