How many oto's could go in a 40g?

[texasblitzem]

I have a three week cycled planted tank with 3 apple snails, a platy fry, and two small oto's. I'm starting to see some algae and love watching the otos do their thing. If I don't get any other fish, how many more otos could I get?

Marineland 350
2x39watt T5HO

 

[texasblitzem]

heres the tank, lots of bacopa and anubias.

 

[Bobby56]

Nice tank! Sorry off subject but what kind of substrate did u use?

 

[texasblitzem]

50/50 Floramax and black sandblasting sand, with a handful of some normal sized black gravel sprinkled on top.

 

[Bobby56]

Thanks that looks really nice!

 

[texasblitzem]

Thank you, it's my first planted tank. I have a chair positioned right in front of it and sit there forever, awesome time.