Snakeheads don't need melafix to heal up. All they need is stable water conditions. In addition, you don't really need any sort of ferts for yous plants. Your fry provide enough nutrients for your plants. Ferts will not trigger anything from the snakeheads. You also don't need to feed the fry, as mom is feeding them about twice a day. The food you feed won't really do much for them at this point anyways. Also, you really shouldn't use a filter for your fry tank. There a different options(much better for fry) that are much, much cheaper than the filter you are using and killing your fry with. Here's the reason why your snakeheads are fighting. The reason is simple. They are snakeheads, and that's what they do, especially after breeding.

I've heard of people lowering temps and also throwing a blanket over tank and no lights for a few days a week.
Sucks we don't understand breeding habits of this fish more clearly.
Perhaps larger tank is quickly needed.


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Look at the sponge filters at both ends of the tank. Total cost (US dollars converted from NT) $20 including air pump, two filters, and airline. I had 300+ fry that were 4-5 cm in there a few months back. Ammonia was 0, nitrite was 0. The plants did most of the filtration. Dwarf snakeheads are not messy eaters. They need very little food, and get fat on a small amount of food. You don't need a canister filter. Plus, sponge filters don't suck up fry, easy to clean, and cost a fraction of the price of your canister filter. Oh, and your new 75 gallon is way overboard for your pair of gachuas. Mine are in a 40 gallon breeder, and that is plenty. Many people have breed them in 20's like yours. You can breed much bigger species of snakeheads in a 75 gallon.
So my 375 GPH Canister Filter is more than enough to accommodate my Channas ?
I've always wanted a big aquarium and i'm getting one, period
My 75G is 48" Long x 20" Wide x 18" High, with from glass made of Starphire and all glass is 3/8".
Now the only thing i need to figure out is what kind of light fixture i need and the bulb that goes with it.
View attachment 811920
Look at the sponge filters at both ends of the tank. Total cost (US dollars converted from NT) $20 including air pump, two filters, and airline. I had 300+ fry that were 4-5 cm in there a few months back. Ammonia was 0, nitrite was 0. The plants did most of the filtration. Dwarf snakeheads are not messy eaters. They need very little food, and get fat on a small amount of food. You don't need a canister filter. Plus, sponge filters don't suck up fry, easy to clean, and cost a fraction of the price of your canister filter. Oh, and your new 75 gallon is way overboard for your pair of gachuas. Mine are in a 40 gallon breeder, and that is plenty. Many people have breed them in 20's like yours. You can breed much bigger species of snakeheads in a 75 gallon.