1. any evidence for nitrogen
2. limitation in zooxanthellae ?
3. Eppley & Renger (1974); negative; isolated Pelley & Bannister (1979); zooxanthellae have lower
4. Wheeler (1980); Parslow et at. uptake activity than cultured
5. (1984) ; Schlee & Komor zooxanthellae (see Gunnersen