What algae-eating fish/invert would you recommend for a small tank (15 USgal)?

[ReyK]

I've got a developing algae problem in my 15-gallon column tank. There are a couple factors that could possibly be contributing to this problem, but the most likely culprit is the fact that in the afternoon, it gets lots of indirect sunlight, even with the curtains closed. I clean the tank walls weekly or sometimes biweekly if I forget or get too busy, but the brownish algae just keeps coming back, so I'm trying to find either a fish or invert that can help me combat the problem. And before you ask, moving the tank isn't an option because the counter it's on is the only place it both fits and can hold the weight of the tank (estimated about 120-140lbs)

For my clean-up crew, I currently have three ghost shrimp, a rather large black mystery snail, and a random baby snail that I think is a nerite. The other stock is one betta (very docile, does not nip fins at all), one male and two female guppies, and one adolescent guppy I am unsure of the sex yet. What should I add to help combat this problem? I'm thinking of getting 2-3 more mystery snails, unless there's a better option. I also plan to get 1-2 more female guppies as well.

PS- I read that corydoras/dwarf corydoras are good cleaners, but I wasn't sure if they'd do well in my tank since the dimensions are 13.5" long by 13.5" wide by 19" tall. That makes a footprint of only 1.25 square feet, which is pretty small, especially for fish that are generally bottom dwellers. I do have rocks and a cave that adds a little surface area, but not much.

 

[Fresh2o]

What type of lighting do you have on this tank and how many hours is it on per day? You could simply reduce the number of hours the lights are on and see if there are any improvements.
Do you have a pic of the algae? I know you are looking for a solution that will consume it, but perhaps there are things you can do to prevent it from growing.

 

[schpanky]

Snails are always cool. I have 5 Otto Cats, I'd recommend them. They're cute, adorable, tiny and they hang out together and clean glass all day. That sun thing is usually the culprit, I had the same problem with one end of my tank. I finally had to put a fake scene/background on that side to eliminate the algae. Maybe you could cover that part of the tank during the "direct sun-time".