tench

Question
hi there i have two five inch tench in a tank with some gold fish. my tench have stop feeding and just sit on the bottom i have tired some live food from the pet shop as well. all so hen i go near the tank the tench go mad they swim at full speed at the glass head first but i don't know why can you please help

Answer
Hi Paul;

Fish can be nervous and stop eating if they are new to the tank or other new fish are added to the tank. It can take a few days for them to settle in. They can also be very skittish if the tank is too small for them. You didn't mention how big the tank is but a 5 inch fish should be in a tank no smaller than 20 gallons. I don't know anything at all about "Tench" but if they are hyper and get large, they may just need a bigger tank. Provide more hiding places for them such as plants to help them feel more safe.

I would also look at the water chemistry. If ammonia, nitrite or nitrate are elevated the fish can become agitated due to poisoning by those toxins. Make a 25% water change and have the water tested. If the tank is fairly new or there were new fish recently added, or the tank is overstocked, toxins could be elevated.

Another possibility is parasites or other type of infection. They can really make fish very nervous and edgy. Look closely at them to see if there is anything unusual such as spots, dots, or patches. Test the water too because elevated toxins can cause the appearance of disease.

At Your Service;
Chris Robbins