Both goldfish and plecos create alot of waste. Goldfish should be kept in at least a 30 gallon tank to allow for growth as they become quite large. Most varieties of Plecos become quite large and also need a tank that will accomodate size as they grow.You should vaccum and do PWCs at least biweekly. In your case every week should do.The bigger the filter the more water it turns over. A second filter isnt a bad idea or the next size up. Also there is a product by seachem called Purigen. It is a little expensive but I have heard good things about it. It comes in pouches for your size filter and will fit instead of , or along with your activated carbon.

I agree - those fish really need more space.

With my goldfish tank, I have to do weekly water changes (25%) to keep things in check. It's the one tank I can't get away with being laxed about water changes - and I have two filters set up on this tank because it's actually overstocked with 4 fish (fancy, ryunkin and orandas) It's only a 42 gallon tank.

Woeisme and skygee, thanks for all the good info. I can just imagine you have had your fill of cloudy water questions!

Well, I could replace the goldfish. As they grow bigger I would assume the situation will just get worse. Would they survive in a pond? (I have access to one with koi in it.) If not, my local pet store has been known to accept healthy fish.

I like the pleco and really don't want to replace it, and he helps keep the tank clean. It gives the kids something to look for, and we've been measuring his growth this past year.

If I get rid of the goldfish, any suggestions for easy tropicals? How about a couple of angel fish or tiger barbs? (No guppies.)

It's nice to have larger, active fish for school aquariums, not little drab ones that hide. I have a heater.

Plattys snd swordtails would be OK [not too many]. Maybe a few neons.

You can do the ever popular betta as the center fish and maybe a small school fish like neon,or cardinal tetras. The pleco if not a smaller variety will out grow the 10 gal eventually.

Goldfish need 10 gals per fish. Veiltails can not go into a pond. The Pleco can not stay in a 10 gal tank since they can grow to 18 inches. Some Plecos like the Bristlenose stay smaller but I would not keep it in a 10 gal.
Angelfish grow to 6 inches and the min tank size would be 20 gal. The tiger barbs are schooling fish and they say that they should be kept in groups of six. They need room to swim and they usually harass everything else in the tank.
A ten would not be good for them.
If you want "large active" fish your going to need a bigger tank.

I see you're in a warm zone. So the veil tails could go in the pond. The only issue with mixing them with koi are that the koi are faster at getting the food. If they're in good shape, I think you should go ahead and trade them.

I love watching cardinals and neons school. They really are very pretty fish.

Glass cats are also nice schooling fish - and your kids will be fascinated by the idea of being able to see through them! They're fairly hardy fish as well.

Well, I'm not sure yet what I'll be doing about the aquarium, but y'all have offered a number of ideas, and I thank you!

I have 6 med size goldfish that I saved from a bait shop in a 20 gal tank but their water is clear and they are all healthy is this ok for them? I also have 3 big goldfish. At least I think that they are goldfish in a 29 gal tank and I keep having problems with cloudy water. How do you clean the rocks? My fish seem to get sick over little changes and I dont want them to get spooked or anything.