AiR BuBBles

[sapgranth25]

I`ve notice throw a day AIR BUBBLES are forming under the gravel,

i notice it between the glass & gravel at the bottom of the tank i use my glass cleaner/scraper each day to push the gravel back to let the air pockets escape but it soon forms again during the next day are so just wondering if this is normal for air to keep forming within the gravel should i be letting it escape are can i just leave it why is this happening................

[Lobo.]

what type of filter do you have?

this could mean that you have anerobic activity in the gravel, or that there is a leak on the bottom of the tank, make shure its not a leak, if its anerobic activity, then stirr the gravel to get oxygen to the bottom of it

[sapgranth25]

well there is no water coming from under the tank are any of the joints i have a trickle wet/dry filter

[Max]

I'd sort of guess that it biologica activity . There isn't much anoxic area in grave for the bacteria to change nitrate to nitrogen but, from your description that would be my guess. Either that or it's catching bubbles from your skimmer etc.