Last night Platy swimming sideways

[Deacon22]

Last night one of my MM platies were swimming sideways and it appeared it had no dorsal fin. Thought I would wake up to a dead fish.

This morning the fin is back and the fish is swimming fine.

Checked the water just to be sure. 0 ammonia 0 nitrite 0 nitrate.

Any ideas why the fin was gone?

BTW...8 weeks in a fish in cycle. 20 gallon with AC 50 and Top 20 filters. only 5 fish in the tank.

Ammonia has never risen past .5. nitrite never risen past .25. and nitrates really haven't shown up.

 

[Calypso77]

Ya if you have no nitrates the tank is not cycled. Not too sure what that would be with him. Just keep an eye on him.

 

[librarygirl]

What fish are in the tank besides the platy? Any chance for aggression among the fish? What are you feeding and how often? Some fish can get swim bladder issues depending on the type of food they are getting, along with other factors.
What test kit are you using? Strips aren't very accurate. If you're using the API kit, you need to shake and bang both nitrate bottles for 30 seconds (I slam mine on the palm of my hand but a hard surface would work too; this breaks up the reagent powder in the bottles and if not done correctly can case inaccurate readings), then shake the tube vigorously for 60 seconds then wait 5 minutes for the results. I would think by now you'd be close to cycled if not already. The fin was probably clamped so you couldn't see it, which is a sign of distress. How often do you do water changes? What dechlorinator do you use? If everything checks out, I'd keep an eye on it and make sure there aren't any other fish that are picking on this one. You could also feed the fish some thawed, deshelled frozen peas (remove any uneaten peas after a few hours) then fast for a day or two; if it has a swim bladder issue this sometimes helps.

 

[Deacon22]

What fish are in the tank besides the platy? 3 other female platies

What are you feeding and how often? Flake every other day

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What test kit are you using? API which I shake and bank forever.

I would think by now you'd be close to cycled if not already. One fish forum said that I have extremely clear water with a lot of filtration for four fish.

How often do you do water changes? 5 gallons everyday in the begining. Now every other day or so.

What dechlorinator do you use? None, I let the water sit and I have well water.

I think it is the fish. One MM platy seems to be a bit aggressive.

Just checked again, the fish is fine today and the fin is still around.