Alk drop after adding sand

[Vmacisback]

Wondering if the addition of sand to my reef is the reason for my ALK dropping. CAL and Mg are staying normal but after adding sand about a week ago I went from my normal rang around 8.1 to 7 to 6.72 all checked with Hanna checker. This all happened in a weeks time maybe 8 days. I just keep increasing my dosing pump to keep up and manually dosing 5ml at a time per day but it seems im on the losing end. Ive read that the increase in bio-load can have an effect on Alk consumption...is this more likely thank the addition of sand? Live sand to be exact. Thanks

 

[Randy Holmes-Farley Verified Community Expert]

The effect of added calcium carbonate sand is fairly small, but could be measurable. It is usually a short term effect (a few days), if there is one. What happens is some calcium carbonate and magnesium carbonate may precipitate onto the fresh CaCO3 surfaces before it gets a chance to get clogged up with things like magnesium, organics, phosphate, etc.

If it is an ongoing increased demand, that is likely from more calcifying organisms.