[soulman]

I have a 4x2x2 with 180L sump that I want to use as a mbuna tank. I assume I can fill the sump with suitable media and use it instead of an external filter?

In Sheffield our water is very soft with a ph of 7.6, what do I need to do to make it suitable for mbuna? Finally are mbuna a good choice for a first cichlid tank?

 

[DJRansome]

Mbuna like yellow labs are a good choice for a first cichlid tank. pH of 7.6 is OK...what is your KH?

 

[soulman]

Not sure I'll have to get a test kit, only got kits for marine. Can I use the Eheim kh buffer if it's low?

 

[DJRansome]

No need, for KH use baking soda. For GH use Epsom salts. But pH of 7.6 is fine so if it is stable I would not do additives.

 

[soulman]

I've been keeping tropical and then marine fish for a few years and the pH has never really changed from 7.6, if it does it's by an amount that can be seen as test error (never been above 7.7 or below 7.4 in what must be 150 tests)

 

[soulman]

No need to use Limestone as rock work or crushed coral as substrate then? I've been keeping the marine tank at 9.2 kH as it helps with algae control and coral growth.

 

[DJRansome]

I have not found it to be effective in raising pH or KH but it is not harmful.

 

[Mcdaphnia]

The pH has to be low for calcium to dissolve into water. By the time the limestone or crushed coral contributes calcium, the pH would already be affecting the fish. Established rock has a biofilm that makes even that ineffective by sealing off the rock surface. If you like the look, it will do no harm.