Otocinclus: Tank Size, Tank Mates and Setup
A small algae grazer for planted tanks. Keep a group in a mature tank of 20 gallons or larger.
- Minimum tank
- 20 gallons
- Temperature
- 72–79°F
- Group size
- 6 or more
- Adult size
- 2 inAll levels of the tank
- Add only to an established tank with algae to graze; it often starves in new tanks.
Otocinclus sp.. Figures are commonly published care ranges; see how it works.
How many otocinclus per tank size
The most you could keep if otocinclus were the only species. Open a size in the builder to add tank mates.
| Tank | Otocinclus, kept alone | |
|---|---|---|
| 5 gallon | Too small (needs 20+ gal) | |
| 10 gallon | Too small (needs 20+ gal) | |
| 20 gallon | Up to 18 | Plan this tank |
| 29 gallon | Up to 29 | Plan this tank |
| 40 gallon | Up to 40 | Plan this tank |
| 55 gallon | Up to 55 | Plan this tank |
| 75 gallon | Up to 75 | Plan this tank |
What you need for otocinclus in a 20-gallon tank
A starting setup: 6 otocinclus in the smallest standard tank that suits them.
20-gallon tank
- These fit a 20-gallon tank and get along. Aim for about 76°F.
Equipment, sized for this tank
Starter supplies
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Otocinclus tank mates
These share a temperature range and temperament with otocinclus, with no warnings from our checks.
Use caution with: fancy goldfish. Add them in the builder to see why.
Plan a tank around otocinclus
Add tank mates, check the stocking level and get the equipment sized for your tank.
Open the tank builderOtocinclus questions
What size tank does a otocinclus need?
At least 20 gallons for a group of 6. A larger tank is more stable and gives you more choice of tank mates.
How many otocinclus can I keep in a 20-gallon tank?
Up to about 18 if they are the only species in the tank. Fewer if you add other fish.
Do otocinclus need a heater?
Usually yes. Otocinclus does best at 72–79°F, which is warmer than most rooms. A 20-gallon tank needs about 75 watts in a 68°F room.
What fish can live with otocinclus?
Good matches include bettas, neon tetras, cardinal tetras, ember tetras, rummy-nose tetras, black skirt tetras. They share a temperature range and temperament with otocinclus.