Hi!
When you have filled a new tank with water, small bubbles are common to see.
The gases added to the water are added under pressure, so when they come back out, they take a while to disipate.
Filters will usually shoot out air bubbles, esp. if they have a venturi tube (small straw thing that sticks above the water surface). This helps agiate the water surface and oxygenates the water.
If you have just filled up this tank, you may get a bacterial bloom, these are common - just a result of everything in your tank getting up to speed. It will clear; may take 2 days, may take 2 weeks, but with your frequent water changes, everything will be a-ok.
Have a read of the beginners topics posted in the FAQ section - they cover most of these in better details.
GL