2 mollies in a bowl

[SLuRpIe!]

i had 2 mollies suffering from swimbladder into a bowl so i could treat them for a while withough hurting the pleco's with salt, the water temp is 80 without the heater for now.. im a little concerned about what caused it, if its the water than i definitely kent put it back, do i do a major water change? i just did one 2 days ago, with siphon, 25% of the water or 2.5 gallons. How do i find out if its the flakes, freeze-dried causing the problem or just the water condition.. i need them to be in the bowl or in the tank for at least another day so i ken purchase an ammonium, nitrite, nitrate tester - so the question is, do they go in the bowl or in the tank?