HELP my 2 little gold fish are swimming sideways and floating :(

[Babyluv]

As the title states ladies my 2 goldfish are swimming sideways and keep floating to the top of the tank.
I just changed the water thinking this would help, I last changed it about a week and a half ago.
I use the conditioner and hardener additives and feed them every 2 days, the stuff that fixes the ph level.
They are in about an 8 litre glass fish bowl.

Please help I don't want them to die.

[Lulu]

Feed them bits of peas. No I idea why it works but it does.

[Babyluv]

Thanks I'll give it a go!