I have a 15 Gallon tank with two Cherry Barbs and one Gold Barb. I've had one Cherry Barb for two years, and the other, male, Cherry Barb and Gold Barb for three and a half (years). They are all very small but have always been healthy. I changed their water in full
two weeks ago; recently added more fresh (distilled water; also used NovAqua+ Water Conditioner two weeks ago). Their filter in their Whisper Filter is also new/clean. Their tank is in front of the window - open to sunlight in the morning, closed the rest of the time. I have two 15W incandescent bulbs that are on often - pretty much except for at night. I feed mainly TetraMin tropical flakes .... I've done everything pretty consistent, right down to partial and full water changes, feeding, lights on/off, etc. Their water temp is always around 80Â°. I have not tested the water recently.
The problem - Last night my male barb began swimming erratically and sideways, and appears to be breathing heavy. I thought he was dying, but he continues to swim sidewards, floats to the top, then regains some control and swims straight briefly before twirling and swimming straight up and down and/or sidewards. However, if can keep himself still he will eat. I feel awful because he eats and/or tries to eat, but cannot stop from spinning, and can't swim right on his own. I hate watching him like this and I'm not sure what it is, if it can be fixed or if he's dying. I'm taking water to be tested a pet store, but in meantime, any advice would be appreciated. I've never lost one before.
Thanks in advance