Low or High?

You can replace those incandescents with small spiral CFL's (cheap at walmart/target/etc.). And you'll still be low tech. And low light. But I'd make sure to pick up a couple oto's for the inevitable algae.

The CFL should be 6500K or higher for optimal plant usage. This is still considered low light.

Should i wait until after i see algea to buy my otos? Becuz my tank is cler of algea now bcuz i just started this one.

It's best to wait until a tank has fully matured before adding Otos. Matured means long enough that the water parameters are completely stable, and long enough for a decent biofilm (aka aufwachs) to grow on all the tank surfaces. Aufwachs make up the majority of Oto diets.

However, you can also help Otos out in a newer tank by being sure to feed lots of green veggies and/or grow algae logs for them. www.otocinclus.com is a good resource.