New member... About to throw my calcium reactor out the window

[Seajackalope]

Ive been on reef central for a week and I've already gotten advice that helped me tackle a problem in my seahorse tank... Now on to the next issue I need some advice on. I have a 300 gallon mixed reef tank that I'm running a calcium reactor on. The pH in my dt was 8.2 before running the reactor. Now I'm around 7.9 during the day dropping to 7.75 at night. I have a 20 gallon ato reservoir and a tunze osmolator. I've been trying to get the pH up by adding kalkwasser in the ato. Currently I have 6 table spoons in the ato and my ph has actually gone down a little rather than up. It typically takes about 4 days to run through the ato water. I have a small refugium that I'm running the light opposite of the dt lights. I have a few questions

1 should I stir the kalkwasser in the ato since it's taking 4 days to empty? I wasn't and the kalkwasser seemed to have no impact. I've since stated stirring it a little and when the ato kicks on the phone jumps up about. 05 then drops right back down.

2 is 6 table spoons nowhere near enough to get the jump in pH I'm looking for?

3 is chasing 8.2 pH in the dt not worth this effort? I have some sps in the tank thats doing OK but I'm not seeing much growth right now.

4 there's a piece of me that regrets getting a calcium reactor and I'm considering just dosing 2 part which would make my 1k investment in the calcium reactor setup blown money... Not to mention the 500 that it would cost to get the dos and reservoir for the apex.

Btw I forgot to mention I have an mrc dual chamber reactor... Which I bought since I thought the 2 chambers would help with the pH issue. The effluent is dripping into the return chamber in my sump. I've been told that doing things like adding an air stone or having it drip into the skimmer chamber will have a very small effect on the dt pH. I'm keeping the pH in the reactor between 6.72 and 6.65 using a pH probe from my apex.

Thanks in advance for any help you can offer.

 

[Greg 45]

The dual chamber reactor does nothing to increase the ph after the first chamber.

 

[SFish]

Doesn't this stuff settle out in your ATO?

 

[Realposition]

I would try making your ATO water fully saturated with kalk. At 6 tablespoons (18 teaspoons) for 20 gallon reservoir you are less then half way to fully saturated. 2 teaspoons to 1 gallon of freshwater will give you fully saturated limewater. If that is enough to keep your PH a little higher at night I would leave it at that.

 

[Seajackalope]

Hey guys. Thanks for the replies. The stuff does settle out in the ato. I guess I'm confused (as usual)... Some people seem to say let it settle and don't touch it. I read other posts that say they stir it. And then you have a kalkwasser stirrer or reactor in which the kalkwasser is obviously being stirred... So I guess I'm asking do you stir or not?

Larry thanks... I'm obviously far away from saturated. I'll get it to that ratio and see what happens.

 

[vikinglord13]

Sounds like the drop in pH is due to the CO2 used in the calc reactor.

Just to cover the basis, have you changed your salt mix since you added the reactor or is it the same?

 

[Seajackalope]

Same salt. Red sea pro. I have two tanks. Both use the same Rodi water and salt. 8.2 in the tank with no calcium reactor. 7.9 in the one with the reactor. Clearly it's lower due to the co2 the reactor runs but I'm getting various opinions in whether I should chase the perfect pH or if it's not that big a deal.

 

[Realposition]

If you are using kalk in your ATO reservoir you want to put it in, stir it up and then let it settle out. You only want to dose the clear liquid after it settles and not the stuff that precipitates and settles out on the bottom. A kalk stirrer is a bit different where it is being stirred constantly but very very slowly so it avoids kicking up any of the kalk or impurities that settle on the bottom.

 

[dendrite]

Have you tried lowering the drip rate from the CR, thereby lowering the pH in the reactor, raising the effluent dkH, and lowering the controller pH trigger point to 6.3. This might allow you to reduce the flow of CO2 and raise the pH in the tank. There's a great thread here that covers use of Masterflex pumps in setting up CR's, but it also goes into detail in some of the many many posts on regulating the reactors

 

[Seajackalope]

So when you say lower it... To how many drips per min are we talking? I was at 30 per minute

 

[dendrite]

That's hardly any effluent at all, especially for a large reactor like a MRC dual chamber and a large tank/sump volume. I run 60cc's/min effluent at 6.4 pH with solenoid controller shut off at 6.3 pH on a heavily stocked 180/55 gallon system with a MRC single chamber reactor. DkH runs between 8 and 9. I don't check my pH because I probably don't want to know. Perhaps your CO2 rate is too high for the effluent and not dissolving in the reactors but being expelled directly into the sump.