Planning to buy a T5-HO Dual Lamp Fixture

[mrhasan]

Hello,

I am planning to get a Coralife Aqualight T5-HO Dual Lamp Fixture (2x31W) for my 20L tank. I was just wondering whether it will heat up my water. Currently, I maintain mine at 78F and have no coral (just two clowns, a brittle and a chocolate chip star). Will the temperature hit above 78F with this fixture?

Alongside, I run my light for 10hours daily. Will this hit the electricity bill badly? Because I live in a rented student home and really don't want that :P

Thanks