Fish Fry (that’s a baby fish, not a taco filling… yet)
The fish are due to arrive in 3 weeks. 1500 baby tilapia fry. They will weigh approx 1/2 gram each and be about 1 inch long. The biggest challenge to raising Tilapia in the Pacific Northwest will be maintaining warm water temps (ideally 70 – 85 F). The average water temp in the main tanks this week has been 55 F. That’s pretty much a lethal temp for Tilapia.
Our plan is to initially raise the young fry indoors (in the strawbale dorm). We
‘ve set up two 100 gallon
feed tanks to start them off. There is a submersible pump in each tank (approx $30 each) which pumps the water into a plastic bin full of filter media. Basically filter media can be anything with lots of surface area for bacteria to grow on. Besides the physical aspect of the filter keeping solids from going back into the tanks, you want a colonization of bacteria to deal with the removal of ammonia through a nitrification process.
The water gravity flows back into each tank. If the pu
mp stops working, the water stops flowing back. It’s really important to fool proof your design. I try to remember that “what can go wrong, will go wrong
“. I would hate to wake up to having all of the fish dead in two inches of water, or the tank overflowing and the fish dead on the floor. Both possible if the system pumping and returns are set up differently.
Right now we have two 300 watt aquarium heaters in each tank to keep the temp around 75 F. I go them on Ebay, made in China. Check out the photos. I especially like the plastic molded cat head on their tops. Not to mention the humorous translations on the box. I’m going to experiment this week with using timers and different settings on the heaters to mimic the daily fluctuation in temp that will be part of their lives in the main tanks. I figure that might be a good way to “harden them off” before they move to their permanent home in the greenhouse.
That’s all for now. More to come.