today i bought 10 Red Eye Tetras and 2 loaches (the kind that look like an eel im not sure the exact name). I would like to get some catfish, and some comet goldfish too.

other than these 4 listed species, what do you think would go well in my 29 gallon tank?

I also need a suggestion on a sucker or snail species to keep my tank walls clean!

Avoid the goldfish. 29G may seem large enough but with 10 fish already, it wouldn't be advised as they produce a lot of waste for their size (and they're already big enough to start) and it's generally recommended not to keep them in anything under 50-55G or so. Plus they generally don't mix well with tropical fish who require higher temperatures.

I would suggest getting a few more loaches (they like groups) and getting another school of a fish similar to size and temperament (peaceful) as your tetras. You could also get a school of Oto catfish. They are entertaining to watch and very peaceful, but also susceptible to random deaths and some claim they are not hardy since they can be intolerant of changes in water parameters or harsh water parameters in general.

Danios, another tetra species, or some barb species would also be a good complement to your current tetras.

Also here is a useful website that you can use a guideline for stocking your tank. AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor

EDIT: If you want to keep your glass clean the best way is to clean it yourself. Plecos/snails are nice but produce a lot of waste for their size (and snails can eat plants if you have them). I think it's best to buy Plecos/snails if you like them - not solely to employ them in a cleaning role, which they can do well but also can disappoint. The Oto cats that I mentioned are good at cleaning the glass, they eat brown algae which many other cleaning fish avoid, and don't produce a lot of waste as far as I know. But I'd still only recommend them if you like them, and they do best in groups of 6+ like your Tetras.

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30G planted aquarium with Aquaclear 50 and two Aquaclear 20s. 7 Cherry Barbs, 12 Cardinal Tetras, 1 Albino Bristlenose Pleco, 1 Golden Honey Gourami, and a handful of Ghost Shrimp.

I wouldnt reccomend the comet goldfish as theyre not tropical fish and prefer low temperatures,the loaches and the tetras are tropical fish,so it wouldnt be a good idea to mix them.

For sucker fish, Bushy Nose Plecos are great. (Or Albino Bushy Nosed Plecos.) You could even get a Nerite snail or two, (Zebra, Olive, Horned, Onion or Virgin.) They are great algae eaters! And, their eggs need brackish water to hatch, so you won't be over populated with snails.

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20g Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981
36g Bow Front Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981

holly got it right with the nerite.. (rhyming it up lol).. they work very well with algae... as previously mentioned, you're probly going to be doing the wall cleanings.. cory catfish work well to help clean up the floor.. Plants work well to keep the nitrates down.

There must be a thousand combinations that would work but you've gotten some good advice already. One thing I would add is to keep the stock load low. The one inch of fish per gallon is not really valid. The fewer fish you have, especially at first, will help keep your fish healthy.

Plants are great, for sure. I have two planted tanks and will most likely plant my 60g soon but do require some thought, light and care. Consider 2-3 watts per gallon about right for planted tanks, more if the tank is deep.

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60g tall, all artificial plants, Rainbow tank; 55g for African Cichlids. 20g long for fry; 20g hex, 2 black Angels at my desk; 10g planted, with 50 Molly fry; 10 gal, 2x 13w cfl lightning, planted; 2g hex for "Buddy the Betta"; Wanting a 200g +, MTS getting bad.

I LOVE cory cats and am thinking of getting some for my 36g. The only thing I was disappointed to learn, is that they aren't algae eaters. They just eat left over food on the floor of the tank. (They look like they would eat algae, but apparently not.)

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20g Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981
36g Bow Front Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981