High dKH, low Ca ?

[bourbeaue]

My tank has been up for a few months. I have added a calcium reactor about a month ago. For some strange reason, my PH is doing fine, my dKH is through the roof (26 !!!) and my Calcium is low (140ppm). Should I be increasing the amount of effluent from my reactor to get more calcium or is this going to take my dKH even higher creating problems ? What is worse, low calcium or high dKH ? My tank does not look great. I have quite a bit of algae on my LR and my substrate is clumping and hardening. In some places, it has become hard as a rock.
I forgot to mention I just added a Phosban reactor although my Phosphate is very low. Just a few other pieces of info, I am running Ozone (around 25mg/hr) and carbon 7/24.

Needless to say my corals don't seem to be loving it...

Help !

[bertoni]

The first step would be to confirm those measurements, since test kits have been known to have problems.

Once you're fairly sure about the measurements, turn off the reactor for a while and let dKH fall to something reasonable. Then, dose calcium up to something reasonable with some calcium chloride, like Turbo Calcium or Dow Flake. This calculator will help with a dose:

http://home.comcast.net/~jdieck1/chem_calc3.html

Since the animals aren't doing well, I'd start some 20-25% water changes, if possible, to help get the parameters in line more rapidly. That could be started now.

This article covers calcium and alkalinity problems in detail:

http://www.advancedaquarist.com/issues/nov2002/chem.htm

Is any sort of buffer being dosed into the tank? pH buffers are infamous for causing this type of problem.

[bourbeaue]

I think you put your finger on it. I did dose Seachem marine buffer several times when first starting up the tank as the PH kept falling all the time.

So water changes en masse is what I should do ?

[bertoni]

The Marine Buffer is particularly bad since it contains a lot of borate. It's intended for fish-only tanks. I would suggest ditching that product and doing a number of water changes. Personally, I would still get a second opinion on the test kits.

[bertoni]

Oops, meant to post this link:

http://reefkeeping.com/issues/2004-09/rhf/index.htm

That article covers low pH problems, which are usually due to high CO2 levels or a problem with the testing equipment.

[bourbeaue]

You would suggest I buy another test kit to double check the dKH and calcium levels or simply test again with same kits ?

[bertoni]

I'd get or borrow another test kit. A local fish store might be willing to run a couple of tests, too.

[bourbeaue]

Thanks a lot. I will take action tomorrow. I was hesitating to do too much of a water change as I noticed recently the output of my RO/DI has degraded to about 50ppm (used to be 0). I have ordered replacement filter cartridges and I am worried a sizeable water change now might introduce chlorine or other compounds into the tank. I will mix another batch of saltwater tomorrow anyway as I assume chlorine would evaporate anyways in the aeration process.

[bourbeaue]

One more thing, assuming I can get my water parameters back in order, is my substrate going to loosen up by itself or am I going to have to replace it ?

[bertoni]

You will have to replace it.

[bourbeaue]

Thanks for the advice. Much appreciated.

[bertoni]

You're welcome! Good luck!