My new phosphate article has posted

Randy Holmes-Farley · Mar 22, 2015

Tests detect inorganic phosphate in the water. Certainly they do not detect phosphate that has been removed from the water for any reason, such as being taken up by macroalgae, bacteria, or higher organisms, or precipitated onto GFO or lanthanum.

VicD81 · Mar 24, 2015

Ok so if test indicate O it really is zero. The reason i ask is because ive seen several post of people saying, "your nutrients are not at 0 because your algae is taking it in", but i guess it that goes for nuisance algae. Meaning that if one manually removed the algae my No3 and Po4 would climb because there is nothing to remove it and would slowly decrease as the algae grew back.

Randy Holmes-Farley · Mar 24, 2015

VicD81 said:
Ok so if test indicate O it really is zero. The reason i ask is because ive seen several post of people saying, "your nutrients are not at 0 because your algae is taking it in", but i guess it that goes for nuisance algae. Meaning that if one manually removed the algae my No3 and Po4 would climb because there is nothing to remove it and would slowly decrease as the algae grew back.

If tests indicate 0, that just means it is below the detection limit of that kit, which varies a lot kit to kit.

Also, rapidly growing algae, whether micro or macro, can drive nutrients down substantially, but obviously some is present in the water.

In that case, getting rid of the algae would allow nutrients to rise.