[danimal11211]

I know clams like a little nitrate in the water column, and SPS' usually do better in a system void of it. My question is, what is the happy medium, is there a way to suplement the nitrates????

[Ninong]

I don't think you should worry about adding nitrates. Well fed reeftanks have more than enough nitrates to go around. A happy medium would be a tank with a nitrate reading of 1 ppm.

[kevinpo]

I know my makeup water has 3-5 PPM of nitrate but I still get a reading of 0 when testing the tank water because the algae, clams, and corals consume it as fast as it enters. Plus I feed heavily so I know I'm adding even more nitrates from that. Some corals also utilize nitrate directly from the water. So one could logically assume that if you have a reading of 10PPM nitrate you may in fact have much more entering the system but is being utilized before accumilating for detection. A very good reason IMO to shoot for a 0 nitrate reading.

Regards,
Kevin
Reference:
Aquarium Corals (Borneman) pg. 344

[Ninong]

I think I should add a bit more detail to my original answer.

Yes, it is possible for an aquarium that is heavily stocked with clams to be nitrate deficient. It is highly unlikely that most reeftank hobbyists will ever encounter such a condition but commercial tanks devoted to raising clams can sometimes require the addition of extra nitrogen to maintain clam health.

Daniel Knop uses a 0.1% standard solution of sodium nitrate (analytical quality, Merck). One gram sodium nitrate is dissolved in 1000 ml distilled water. From that solution you add not more than 10 ml per 100 liters aquarium water. The nitrate contents of the water must be constantly monitored with the help of a precision instrument and must not rise over 2 ppm. The goal is to eliminate a lack of nitrate, not to raise the nitrate levels.

This is the reason that I suggested a reading of 1 ppm nitrate is better than a reading of 0 ppm nitrate for a reeftank that includes Tridacna clams. This is the recommendation of Daniel Knop, too.