I have just set up my first tank with 3 medium sized Shubunkin. They all seem perfectly happy (only been in there 3 days), but one of them has his fins closed and seems to swim slower than the rest. He is also quite lathargic most of the time. Anyone have ideas why? He's eating fine, and the tank seems to be working correctly.
IF THE FINS ARE DOWN THE FISH ISNT HAPPY HAVE YOU CHECKED THE WATER FOR NITRITE,OR EVEN THE PH,HOW LONG HAS THE TANK BEEN SET UP ? HAS THE FILTER HAD TIME TO MATURE CORRECTLY ?THEY WILL STILL EAT EVEN IF THE WATER PARANITERS ARE WRONG SO CHECK THE WATER