Needeles said:
Keep in mind if you are going to get one that you will still need to feed them with other types of food. Also some "Algae Eaters" will stop eating algae after they get bigger so you will want to check that.
You should also try to figure out as to why you are having an Algae problem. There could be something that needs to be changed. Start a new thread and see if you can get some ideas as to the cause of it.
I totally agree with Needeles. Many folks on this forum, myself included, have a pet peeve where people want to get algae eaters to take care of a problem for them. It's really much more practical to simply scrape the algae off yourself, or as Needeles said, figure out why you have that problem in the first place.
I have a well-balanced 29 gal community tank with healthy live plants. I can leave the lights on in there 12-14 hours a day and still grow very little algae! It took me a long time, but I finally found a good balance of light, fish, plants, and fertilizers that works.
Otos (Otocinclus catfish species) are adorable, I agree, I have 4 myself. However, it can be very difficult to feed them once they eat all your algae. I was scrambling to find alternate foods for them so that they wouldn't starve! I was even farming algae in another tank! Most otos will not touch prepared foods, even "algae wafers." I finally found a true herbivore food that lists kelp and spirulina as the first two ingredients, rather than fish meal or wheat. It's Omega One Veggie Rounds (even their Veggie flakes still have seafoods first before veggies), and they love it! So if you decide to get otos, I'd highly recommend that food to supplement them.
good luck, and feel free to post another thread as our wise moderator suggested