Corraline and KH

[dobelady]

I have no corraline and any I add seems to disappear. I have started raising my kh and it is up to 13 how high is too high?

[JakStat]

Believe it or not, and I wouldn't have before I did this, but my coralline exploded when I lowered my dKH from 12 to 7 (long story, and not for the coralline). I don't know if this was the cause or not however. But it does prove to me that coralline does not need high levels of carbonate hardness to grow.

[Randy Holmes-Farley]

IMO, the things that harm coralline most are elevated phosphate, elevated organics, low alkalinity, low calcium, and possibly low magnesium.

How long has the tank been set up?

Do you have other hard corals that are growing?