Unwell Tiger Barb...Help Please!

[NoWittyName]

Did my 20% water change as usual yesterday (regular Sunday job) and can't think of anything I did differently.

Noticed earlier today that one of my tiger barbs was acting strangely. He (She?) is constantly wiggling as if he's fighting to keep himself in the same place and he's at a strange angle. He just seems unable to rest. His having to use his fins constantly and I just feel like he's struggling. Here are today's water results...

Cl2 - 0
pH - 7.6
KH - 6d
GH - 16D
NO2- - 0
NO3- - about 30 which seems a bit higher than usual.

Had been alternating day of fish flakes,, day of bloodworm cube, day of flakes etc etc, but have been giving flakes alone for a good week because run out of cubes. Could I have been overfeeding and could this have caused it?

Don't want to start losing all my fish if it's something I'm doing or if it's something contagious. :(

PS tank has been up and running happily since November, so not a cycling thing.

Fish all better today?!?!? Very happy, but rather confused...any thoughts still gratefully received.

Sorry, didn't spot this yesterday. Glad he's better, maybe he had a bit of constipation. Best to keep an eye on him just in case.

Poor lad - will pour in some movicol and possibly a dose of lactulose tonight. I wonder what age he is? Adult or paed movicol do you reckon?

I'd go with the paed to be on the safe side. See if you can get him to drink any prune juice and bribe him with chocolate buttons if he's withholding on purpose.

Never even thought it could be a chosen behaviour - think I may have to find a book on how to deal with it appropriately.

Try 'Contented Little Tiger Barb'.

Think I may be more of an 'unconditional fishkeeping' kind of gal.

You're making a rod for your own back, I tell ya.