The water for raising fish stinks.

Your filter tank is very small, and there is only one kind of filter material, sponge. The water stinks because there are no nitrifying bacteria in the water, and whitening proves that the filtration function is not good. If the water tank is more than one meter, multiple filter barrels must be installed. If you make your own fish tank, you can change the filter tank into three layers, the first layer of sponge, the second layer of biochemical cotton and the third layer of glass ring! After the improvement, change half of the water, put water purifier, nitrifying bacteria, water stabilizer, salt and dechlorination and sterilization water.