Hate to break it to ya but there are not too many fish that actually eat poop if thats what your asking. There a few willing to sift through it but off the top of my head I can think of one that actually is known to do what your asking for and it would probably eat your goldfish (green scat) given the choice between the 2. You really need a filter to keep the water clean and you need a siphon to remove waste that hides in the gravel at least once a week.

A PLECOCOSTIMUS ,CORYDORA OR ALGAE EATER

i would say a pleco is the best choice if you have space for it
but a most definite no on the snails they tend to ov er reproduce very fast

PETA people have scouted you out. I would hide.

Seriously, Goldfish are very dirty fish. They pee and poo non stop. The ammonia content in an unfiltered tank would be crazy since it’s stagnant water. At the very least a 10 gallon aquarium with a filter and gravel is a must. Once you have established the tank it will pretty much take care of itself and bring your workload down considerably. Just make sure you don’t go nuts and get 20 fish ….1-2 goldfish in a 10 gallon tank is about all it can handle. My first tank was 10 gallons with an applesnail because I thought it would help. I WAS WRONG! It always tried to escape and laid eggs all over the place.

What? Get a filter! Another fish will just make the tank dirtier.. algae eaters won;t filter the tank for you! And they also poop and eat… I bet your goldfish is in too small a tank, get him at least a 10 gallon with a filter, if you can’t afford that, you should reconsider a pet.

Well unfortunatly you have a lot of problems here. A goldfish in a tank with out a filter is indeed a pain. I have 5 in a filtered tank that is a pain. You could get snails, but they multiply at rediculous rates and QUICKLY become out of hand and a bigger problem than the dirty tank itself. Even one can cause this problem as snails have both male and female organs, so all most all snails you will buy will be ready to lay eggs. A pleco also seems like a good answer but they grow to enormous sizes. They also will not live long if they aren’t provided spiralinia algae flakes or tablets, which often cloud a tank, especially one with no filtration.
Goldfish produce a lot of waste, and ammonia, as I’m sure you already know. This makes it difficult for any other fish to survive with them.
My suggestion is that you purchase a tank (10 gallon probably) if you currently have the little guy in a bowl, and a filter. Petsmart sells the whole set up for like $35. Which isn’t bad. Then for added cleaning you could get a small algae eating “sucker” fish or a cory. You may find that goldfish temperature water (room temperature) could be too cold for the cory cat as it is a tropical fish. But in my experience as long as the water remains in the low 60′s tropical fish do fine without heaters. Be sure to keep an eye on this though.
*A goldfish’s tank should never be brought into warm temperature (upper 60′s or more) unless to treat disease as it has been shown to significantly shorten their life spans

Chinese Algae Eater Info

Cory Cat Info

The idea of a cleaner fish that will relieve you of the duty of cleaning a tank is a total myth. he more fish you put in the tank, the more it will need to be cleaned. Invest in a decent filter instead and you and the fish will be much happier.

MM

i cant think of thir real name but if you till the pet store you need a sucker fish they will know what you are talking about

plecos there nice and help

a bottom feeder and get a snail they eat all the stuff off of the tank they love it they keep the tank clean