Using crushed coral to raise pH - how long does it last?

[MartyMA]

Hi Everyone - I struggle to get my pH into a neutral range. My setup:

20g long, housing a small colony of RCS and a few ramshorn snails. Heavily planted with several pieces of mopani driftwood. Water is moderately hard. I have a bag of crushed coral in the HOB. Been there for a few weeks. My pH wants to be <6.0 and I want it to be closer to 7.5. The crushed coral raised it to about 6.8 or so. The question: do I need to change out the coral at some point to maintain it's alkalinity power or should it last a long time?

Thanks.

 

[MartyMA]

No experience or opinions about this?

 

[librarygirl]

I think it depends on your water; cc will break down differently in each tank. Even it does need to be replaced it can be a while though (months if not longer). The only way to tell I think is just to just run PH tests on your tank every few weeks or month or so and if you start seeing changes then change some of it out. It does also collect some biofilm and such that may affect its performance; when I swish my filter media in old tank water I get the bag of CC and swish it into the old tank water as well to clean it up a bit.

 

[MartyMA]

Thanks librarygirl. The cc does seem to be working okay for water hardness but the pH barely makes it across the 7.0 mark. Not too bad. I am trying to have adequate parameters for my RCS. I should be okay.