Help Sick Tetra?

[dan2x38]

I got 1 of 4 Blackshirt tetras sick. He is barrel rolling when he swims. He did eat this morning. He is swimming fast, has no scales sticking out, no stringy poo, no bloody fins, not bloated, might look a little thin, and was fine yesterday... there seems to be a slightly pinkish area below his jaw towards his pectoral fins. Moved him to a small hospital tank added 1/2 tsp of salt. His tank is less than a gallon I am using all other tanks now for CPD breeding & fry grow out of CPDs. Think I need a 5g or 10g for a QT.... God another tank?

I love these characters hope I can save him! 

[dan2x38]

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