Low Alk symptoms

neupane00 · Feb 12, 2016

I didnt realize that my hanna was consistently showing wrong alk. I maintained it at 7.3 (per hanna checker). After about 2 months, i double checked with Red Sea alk , and it was like 6.8.
I havent seen that detrimental effects on my sps dominated tank (besides slower growth). But wanted to ask experts what are the signs of LOW alk in the system (mostly for sps ). Do they start losing color as well? what else?

Randy Holmes-Farley · Feb 12, 2016

Slow growth is what I'd expect from slightly low alkalinity, but 6.8 dKH is about at the ocean level of alkalinity, so I would not expect any significant harm.

neupane00 · Feb 12, 2016

Randy Holmes-Farley said:
Slow growth is what I'd expect from slightly low alkalinity, but 6.8 dKH is about at the ocean level of alkalinity, so I would not expect any significant harm.

Thanks Randy for ultra quick response.. Now i can rest easy

tristanfish · Feb 12, 2016

Randy Holmes-Farley said:
Slow growth is what I'd expect from slightly low alkalinity, but 6.8 dKH is about at the ocean level of alkalinity, so I would not expect any significant harm.

This applies to lps?

Randy Holmes-Farley · Feb 12, 2016

I would expect so, but as with SPS, there's not a lot of data around about how low alk needs to get before anything more than slow growth results.

psirex · Feb 13, 2016

So low alk for sps?

Randy Holmes-Farley · Feb 14, 2016

psirex said:
So low alk for sps?

What is the question?

I'd consider low alkalinity to be less than about 7 dKH, but would not anticipate "problems" until the alk gets below the mid 6's at its lowest between dosing.

They will likely grow faster at higher alk levels.