Alkalinity decline without coral

[GARRIGA]

Nitrification reduces alkalinity and carbon dosing or denitrification puts it back although WCs will remove the nitrates produced and not allowed to replace what was used during nitrification. Perhaps reducing nitrates before performing a WC will help. I don't do WCs in my test tank and my alkalinity is stabilized around 9 dkh and coming up on a year since last WC. Carbon dose and have a large media bed that is suppsoed to perform dentrification but flow appears to fast but it's working. Hope is once I have my main with corals then only replenishment will be that consumed and not due to nitrification.

 

[keithIHS]

Randy H-F was confident it was going into the sand. I think I recall that conversion of ammonia to nitrate reduces alk and conversion of nitrate to N2 (or uptake of nitrate by algae etc?) increases alk, which is why my dosing nitrate was increasing my alk, and why dosing ammonia is supposed to have no net effect on alk.