Backyard Aquaponics
A place to discuss aquaponics

I cleaned some tilapia tonight to eat tomorrow. I got 8 nice fillets. I'm trying Amaca's trick of salting them lightly and keeping them in the refrigerator for a day. (Do tell me I'm remembering that right?)

You remember it all right.
To wait will make the flesh softer and the flesh cells tighter and the salt will give a bit of taste and protect from microbial activity.
Don't forget to post the feedback, please.
And why not the very clean plates...

I tried two females with one male and one female killed the other. Now I have two males with one female and as long as I keep the tank covered with a sheet, the female doesn't seem too stressed.

She must have been a jealous one.
The rule of diluting as much possible the aggressivity is still usefull.

What i was calling a harem is at least 1-2 males for 4/5 females in a big tank. This way it keeps the males trying to show off and the females don't spend there time bashing into always the same fish. It is the ratios they put in ponds in Africa and Asia to produce fingerlings.
I think that a breeding pair will protect a surface of a sqm when breeding and caring for babies. They are big fish to keep in aquariums.
Anyway I suppose that the breeding pair you have, just push the second male into corners.
If you are selecting further brood stock, go for the calmer ones in the bigger ones.

I agree with you. I only have two mature females left. The others have all been killed. The one I'm working with is the most aggressive. Once I get a third tank set up, I'll try with the shy female.

The female that is in with the males right now seemed ready to lay eggs last Sunday -- she was bulging and had a little thingy hanging down out of her rear -- I'm guessing it was an ovipositor. But my wife wanted me to wait until my brother came so he could enjoy the action -- by the time my brother came, the fish must have started reabsorbing her eggs. But unless she starts looking very stressed, I'm going to leave the males in with her for a while. About a month ago when I tried it last, she was looking very tired and bruised so I took the male out -- two days later she had a mouth full of eggs -- obviously unfertilized. She held them for almost a week before swallowing. The second slightly smaller male is taking some of the male's aggression so she's not looking quite as stressed. My fish are fairly large for breeding in an aquarium. I have them in a 72 gallon bowfront. I'm sure both males are over a pound. The female might be close to a pound. The last brood I got from a fish this size was about 200 fry.

That's a nice size for exotic aquarium cichlids
Hope all will be well, and for the fish don't wait for anything, i've noticed that if you wait when you see something in a fish tank, or the fish die or the spawn doesn't work. Feed them well after the spawn and check water quality because they can get so tired that they can be wiped out by a disease that is in the tank but they could fight.
Are you still feeding them with trout food?
I suppose that you have mixed it with fresh food.

Trout food is all I'm feeding my tilapia right now -- other than the occasional vegetable or leaf of lettuce

The eggs would be better and the fry would grow faster if the food was as fresh and alive as possible.
The growth coefficient of the life of the fish is determined by the speed at which the eggs develop themselves. In fact the first month is the key for fast growth, after that you can feed them sh*t and they'll still grow at fast speed.
It is why they are thinking of doing fish food with leftovers of biocarb and no fish meal anymore for the growing period. They can compensate the slower growth speed because of the green food by the first months in hatcheries with very highly purified fish food.

so what sort of live food would be best for Tilapia fry and breeding pairs. Should I get some duckweed? Green water? Infusoria? Daphnia?

Amaca, The tilapia fillets were good tonight, but not any better than straight out of the tank. I think good living and clean water make up for so much that the salt and 24 hour rest can't improve much.

Ah ha!

I switched fish around in the breeder tanks, and in particular, dropped one very fat female in with another fish I hoped was male. Ta da! There's a mouthful of eggs. So now the question is whether the other fish is really male, and whether the eggs are fertile.

I have one pair in each breeder tank, and I know one fish of each pair is female. Progress! And I do think feeding them frozen peas is helpful.

I've posted this on our member thread but thought I'd also post here in case some other nut got the same idea we did.

Last Sunday we picked up 4 nice sized tilapia from the local Asian fish market. These fish were shipped in from Idaho (we're in Washington - ~500+ miles) and are live in the tank. We brought them home and put them in our fishless system. It seemed like a good idea the first few days.

This morning, the fish look awful. They have large white splotches and battered looking fins. I've salted to 3ppt in hopes of seeing some improvement. I'm not sure if the problem was something they brought in and the travel, water changes, etc. caused the infection or whether it was something brought in on the feeder fish that are now gone from the system. Either way, we're trying to decide our next course of action...

* Pull them and eat them and work on water quality
* Wait it out in hopes they'll improve

In terms of water quality, we are sharing an order from Miama Aquaculture that is to be shipped early next week. We're figuring its a trip to pick them up next weekend. So, we need to get the water cleaned up...

* Complete water change?
* Hope salt will address the issue?

We could also get an aquarium to put the fingerlings in until we get this resolved. That is in the plan anyway for a brood tank.

Thoughts?

I would be inclined to take the 4 fish out and put them in a salted aquarium. If you have the water to spare, dump your system water and replace with clean stuff, ready for the fingerlings. If you are going to do this, do it sooner rather than later to give it time to settle.

actually, can you put the fingerlings in another tank for a couple of quarantine weeks too? salt that as well

I wouldn't want to contaminate your new fish if those are diseased. Remove them and change the water would be the safe thing.