Does your gravel also appear to move? could be malaysian trumpet snails also snail slime attracts bubbles so if u have a fancy filter or an air stone the bubbles will get trapped down there
Hey, its not snails as there arent any in there, its not cabbage or any other vegetables cus i dont feed them any, theres no airstone in the tank, i hve the co2 bubbles going into the filter, but the outflow is aimed strait for the surface!
There mostly along the front of the gravel, on and under it, i thort it was the plants bubbling at first, but then i noticed the bubbles where coming from the gravel
Maybe its the alge growing so fast and making the bubbles ...wouldnt suprise me anyway!