Foamy bubbles in tank!

[Carolinagirl]

Hey guys, another question! I've had my 20 gal tank set up for about a month now and I've done all the cycling for it and its been great, but the past couple days I've noticed bubbles at the top of the tank and last night I noticed some if the bubbles are foamy. Does anyone know the cause of this?

 

[blackmolly]

are the fish ok? have you been dosing any meds lately?

 

[Carolinagirl]

The fish are great... I have 4 glofish and 3 cory cats in the tank and they seem to be just as happy as can be. They swim all over the tank.

 

[Carolinagirl]

Oh and no I haven't dispensed any meds in there

 

[kenbob]

The foam can be caused by excess protein. Try cutting back on feeding.