CaRX question on amount of media

Raoul5Duke

Active member
I recently switched to a Calcium Reactor running off an Aquarium plants carbon doser and a Kamoer continuous dosing pump. Stable 6.5 Ph in the reactor running 140 ml/min and cannot keep up with my alk needs. I hope I just made a dumb mistake in the following, I only filled the chamber half full think it was no big deal I would just have to replace sooner. I assume I should have filled it full. Do you agree? If so is it just as simple as adding more to the CaRx or should I dump the 2 week old media and start fresh?
 
You just add more fresh to what's there.

However, a CaRX isn't meant to keep up Alk demands. When I ran a CaRX, I also ran a Kalk reactor.

What size tank, and what is your current Ca level?
 
~450 total system gallons was using 300 ml of Alk/Ca daily previously but was driving the salinity too high. Tried adding a kalk reactor supplement but it was not keeping levels stable. i can always supplement with the dosers again. Ca & MG were 450 & 1450 last I checked but have been focused on alk last two weeks. Alk went from 8.6 to 6.78 over 11 days
 
Your Ca & Mag are spot on. And as you can see your CaRx is keeping up with your Ca demands. If you increase the CaRx output in the hopes of raising or maintaining Alk, you will drive your Ca level to high.

I don't see any other choice but to supplement the Alk to keep your levels up.

Where you using the Kalk reactor to replace all evaporated water? If so that might be to much. When I ran my Kalk Rx I ran about 50% of the RoDi makeup water thru it, then the other 50% was straight RoDi back to the tank. If you go this route, you can adjust the percentages to maintain a constant Alk level.
 
Last edited:
thanks for the help my assumption is it would keep up with all elements. I will make the adjustments with a dosing program. Haha always the simplest things trip me up should have done a little more research.
 
Have you tested the dkh of your effluent? I'm guessing it's not very high. Which media are you using? Some (like arm coats) requires lower than 6.5 ph to dissolve
 
I was running a korallin C1502 on my 150g system that is mostly sps. The reactor was filled to about an 1/4" away from the pH probe sat in the reactor.
620e24020f8383de494d64a5eb119eab.jpg

Korallin rates the reactor at 400g, yea right I was running it at a beaded stream at pH 6.7 and having a pita time trying to keep my alk and cal at a stable level. I then decided to build my own cal reactor from an old kalk reactor that had got cracked.
5304133cb6ebb3549fe4d3877ffe33cf.jpg

3ef06bfa23ec0adeaab007616ed55a63.jpg

I filled the new reactor with 1 gallon of extra coarse and 1 gallon of coarse media's. So there's around 15lb to 20lb of media in the reactor. I also put in 1 bag of neomag media and the reactor is only about half way full.
06a12576667cce33369b8f4d7485f88f.jpg

So now to the grits and grave of my info

So I know use a masterflex @ 30ml/m and the pH in the cal reactor is set between 7.25-7.30pH and now my alk stays perfectly at 8.2 dkh.

So know I'm a full believer of getting the largest cal reactor you can fit. Even if it's way over rated for your system.

Cause not I use way less co2 and when my frags grow larger then I can lower the pH in the reactor or increase the effluent rate. Another bonus is that now that I don't have to run the pH so low in the reactor the pH of the tank has been higher as well
 
Have you tested the dkh of your effluent? I'm guessing it's not very high. Which media are you using? Some (like arm coats) requires lower than 6.5 ph to dissolve

I did but it was off the chart, the instructions provided above detail how to do this which is on my list to get done and adjust today. Thanks.
 
Back
Top