Yes, i think it was lack of food. I did finally get an algae bloom started in a 300 gallon ibc but it was too late. I can also see the tiny zooplankton swimming around so i think it would have been sufficient if i had it a week earlier.
I drained the outdoor ibc today and there were maybe a dozen fry at the bottom. They are now about the size tilapia fry are when they are born. i wasnt able to catch them. but they may be in a rubbermade tote where i emptied the bottom off the ibc, i will check again once the water settles and i can see better.
Theres no doubt i will try again i just havent decided if it will be this year.
On a recommendation from another site i am going to try to use Spirulina Powder as a starter fry food. I dont think i will be able to generate large algae blooms with all these
Also next time i wont take the parents out of the tank. Since i only need 100ish, i will just siphon out water and capture a couple hundred to place in another tank. Less should be less food competition and easier to keep alive.
brian
