llgrit was hiding under the bench in a brown paper bag, or perhaps that question was not on the survey sheet::-) Seriously though, questioning "the gospel" often livens a debate and freshens up interest in basics that really have never been run past the "
scrutinoscope".
Scott's comment on sex ratios brings back a flood of anecdotal opinion from various ANGFA members over the years concerning the influence of ?pH/?Calcium levels. Several members were convinced that Glossolepis incisus spawnings produced a disproportionat
ely high percentage of males if the calcium /pH was allowed to fall (below an unstated critical minimum) so the general advice was to use a shellgrit substrate over UGF for this species. Similarly for Desert Gobies, it seems that adding calcium (in whate
ver form) and salt (up to the equivalent of seawater) improves the sex ratios towards equality whereas a vast oversupply of females seems to be common in situations where thet are raised in softish neutral to acid water. While we are on the subject of DG'
s, has anyone else seen the phenomenon of sex reversal occurring? A few times when left with a group of females only in a tank of DGs one of the larger specimens has become a functional male and gone on to breerd successfully. These particular males never
became as brilliantly coloured as the primary males. Asimilar process occurs in many marine fishes such as the anemonefishes etc.
Bruce Hansen ANGFA (Q+N)
Attachment Converted: c:\eudora\attach\RE Re[2] Watercalcium