Is everything im doing wrong?

I have two Goldgish and there kinda small but not really small, just normal sized and anyway there kept in a bowl thats not very big but not that small and i feed them twice a day(a pinch of fish food) The bowl has a lid on the top to stop them from jumping out even though my fish are calm and are not very jumpy fish. The bowl has no heater or anything like that and i fill it up with cold water, no warm. They have about 10 colourfull pebbles that they seem to enjoy and often play with them with there little heads. However they have nothing else like a plant or anything. When we got the pebbles the shop person told us not to put to much stuff because it will crowd them and they wont be able to breath properly. We are getting a kitten in a week but i can't get rid of my fish, i love them so much so were thinking of putting the fish on a high cubbard but someone told me that will be ok untill the kitten grows older. Is there anything i should be doing that im not? or anything i shouldnt?