Algae Control

[Gnatfish]

Hello

I have a 15 gallon and it seems to develop lots of string algae and algae on the glass. I am thinking about getting some Ottos to combat this. Are Ottos good at eating string algae?

Also what other ways are there of combatting string algae? My tank's lighting is 2wpg and i do 25 % water changes every 7-14 days?

Stocking:
6 Lemon Tetras
6 Harlquins
2 Cories

Thanks

 

[Gnatfish]

???