Oto Information
Part of a large family of Loricariidae found in rapidly moving rivers throughout most of South America, the Otocinclus spp. are among the smallest species. Oto catfish grow up to 5 cm, which makes them suitable for smaller aquariums. They are usually tan with a black peppered body. Otos should be kept in planted tanks only! They do much better if kept as a small group. Otos are the best plant leaf cleaners and will remove almost all algae from it without damaging the leaf. They will ignore the grown algae, but will eat young algal growth and by doing that will keep the algae very low. Like all catfish, these one enjoy the presence of bogwood, so adding a piece to the aquarium would be a good idea. If there isn't enough algae in the aquarium, Otos should be fed with blanched zucchini once a week, boiled for 2 minutes and cooled down before feeding. Place the zucchini on the bottom or, even better, on the piece of bog-wood where the Oto will come readily and notice the vegetable. Do not leave the zucchini for longer than two days inside the tank and not shorter than a day. It's been known that Otos will ignore sinking catfish tablets and algae wafers, and will ignore most of other vegetables like lettuce, spinach, cucumber, etc. Zucchini is the best proven feeding choice. Some aquarists farm algae and than introduce them as Oto food. It's been known that Otos relish brown algae (diatoms). One of the best ways to ensure that Otos will have sufficient algae is to keep one Oto per approximately 60-70 liters. After observing the algae in your tank for a week you will get the answer for whether or not you need to add more Otos or if they have sufficient algae. Keep a close eye on their stomachs: round bellies are a good sign of algae sufficiency. It is good not to clean all your aquarium glass at once since they will eat the algae off the glass. Otos should be kept with smaller/calmer fish. They like to rest on broad plant leaves and bogwood rather than gravel.
Otos can be difficult to acclimate to the home aquarium, but if provided with correct water conditions and there is some green food they will be fine. The setup should be well established with a sand or gravel substrate, and densely planted with live plants. An established algal growth is essential. While they will take flake food and sinking pellets the natural greens are needed to provide proper health. If no algae is available they will eat soem softer bodied plants. Provide good water circulation and filtering. Best to keep in groups. The actual number will vary upon the tank size. Compatible with most fish except the larger predatory species. Otos live up to 5 years. They need a pH around 7. Water temperature should be around 25°C.