[Delphinus]

Couple of things.

1. Yes, the more blue a light gets, the less overall intensity you get out of that bulb. It only stands to reason. You have fewer wavelengths in the spectrum; thus you have less light. You're not imagining things, this is a well documented phenomenon.

2. A calcium value all by itself is a worthless measure. If your alkalinity is low; then nothing can draw that calcium out of the water column. Calcium is very typically high in situations when alkalinity is low. If you want any value out of a calcium test then you have to test your alkalinity in concert. Maintain a high alkalinity and I guarantee you that calcium goes down. You'll even notice things such as stoney corals and coraline algae growth rates start to increase.

3. Unless you have a mature specimen of tridacnid (and I do not know if anyone really knows the distinction between adult and juvenile all that precisely ... perhaps Daniel Knop would), it is a certain guarantee that clams will starve and perish in captivity without planktonic food. Perhaps a tank has enough of this on its own; perhaps some "help" may be in order.

Good luck, and above all, have fun. Cheerio...

[ 29 August 2002, 22:18: Message edited by: delphinus ]