Alkalinity and Calcium HIGH Calcium reactor not hooked up ye

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.


Aquarium Advice Apprentice
May 24, 2004
Miami, FL
Hello everyone,

About 2wks ago I bought a Koraline calcium reactor. I decided to check my calcium and alkalinity levels before installing it. My levels were extremely high. Ive been doing water changes and I've got it somewhat down. The alkalinity is currently at 14.4 and the calcium is at 550 also my PH is very low at 7.9. I have some stony's and soft corals as well as fish in my 110gallon tank. The test kit I use is a Salifert. My question is should I continue to do some water changes to get the calcium at 450 and the alkalinity at 8 and somehow get the ph at 8.4? Plus remember I still haven't even hooked up the reactor yet. ANY help would be appreciated.

Water changes are about the only way of getting the numbers back in line. Be sure to use well aged/aerated SW. I would suggest posting the chem numbers of the newly mixed SW after about 12ish hours.

What have you been dosing and how often?

I know this is probably a newbie questions, but at what levels of alkalinity and calcium are considered too high and a threat to the aquarium?
SpEd said:
at what levels of alkalinity and calcium are considered too high and a threat to the aquarium?
Anything above NSW chemistry is pretty much unneccessary. As far as dangerous, it really depends on what is in the tank, most affected will be invertebrates but fish as well. Some animals will "weather" higher alkalinity <15 DKH but it does stress them severely. Higher Ca (<500+ ppm) can cause polyp bail out, both can cause RTN and clam mantles will lose their cohesion to shell walls. There is also the high probability of a precipitation event.

Maintain alk at 1.5 - 3 mEq/l with a <<balanced>> ratio to Ca and Mg. Also be sure to test before you add especially until you are very familiar with the tank rate of depletion and consumption of CaCO3.

Top Bottom