We have flies. Tiny ones. We did some research and believe they are midge flies. They magically appeared to torment us about 8 months ago. We gutted the old tank, we heavily bleached everything trying to kill the larva (we were super careful to rinse everything and even rinsed in water with dechlorinator prior to putting the tank back together. Took over 3 hours). Those larva were impossible to kill. We replaced the tank (our girl needed a bigger one anyway). Nothing from the old tank went into the new tank. We tried to kill all of the adult flies we could find before trading tanks. We put the old tank outside. Now we are finding flies again.
Please help! We have pond rocks in the bottom. We're considering getting fish but the larva hide in the rocks.
Suggestions? Anything safe to treat the water?