Over inflated Cherry Barb

One of my Cherry Barbs stopped eating, secluded itself and started expanding in size. He started looking like a seal. Poor thing. Oh well. That's probably the start of dropsy or kidney failure. I put him in a quarantine tank and, using my own advice, put a tablespoon of Epsom Salts to the 7 gallon tank and some daily anti-bacterial. I had expected him to have died a week later. No. His swelling went down and miraculously he managed to eat a couple of flakes today!

What would cause a reversible type dropsy? An intestinal blockage? Maybe he's got weak kidneys and the Epsom Salts are stabilising his problem, which could mean he's a permanent resident of the quarantine tank with MgSO4. Anyone know what the negative side effects of MgSO4 are?

Nikki

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