Corals and Bioload

[rickm]

There are some LPS corals that can be just as hard to keep as SPS. LPS have there own needs as well.

[davejnz]

LPS=large polyped STONEY coral.Just like SPS,LPS have skeletons and require carbonate/bicarbonate/calcium to build them.My old 40gal LPS tank required alot
of alk/calcium to maintain its level at 8dKH and 420ppm.I used full strength kalk dosed 24/7 and i still had to use baking soda(buffer)and CaChl twice a week.
Corals represent a small part of the bioload in a typical reef tank IMO.Like Greg said,they uptake nutrients from the water.They compete with algae as well for those nutrients.Fish and the foods we feed them make up the biggest part of the bioload in terms of Nitrogen production