Bubbles

[Evan]

Hi all. I hope someone can answer my questions.
I have a sand substrate maybe 2 or 2 1/2 inches deep. Recently, after 3 years, bubbles have started coming out of the sand. I assume this is a result of anaerobic bacterial activity within the substrate. 
Is this harmful to the fish? If it is, what are my options?

Thanks!

[Lennie]

It can be cause by ammonia. Detrius and stuff may get stuck below the sand and may cause gas build ups.

Test your water parameters to make sure it ain't causing ammonia spikes first

Edited May 1 by Lennie

[Guppysnail]

Often folks with sand substrate use things like Malaysian trumpet snails to eat what gets trapped in the sand and keep the sand churned since they burrow so anaerobic bacteria does not build to harmful levels. I think what is released as bubbles is hydrogen sulfide but don’t take that as gospel I’m not a scientist. 
Other folks use chopsticks or a gravel vacuum to keep the debris up and churn the sand. 
I have heard debate in both sides of if it is harmful or not. If directly “inhaled” by the fish it is supposed to toxic. Others say it does not dissolve into the water and gasses off at the surface when the bubbles pop. 
When I have used sand I play it safe and vacuum as well as poke chopsticks in areas around plant roots I cannot vacuum. I breed a lot of different snail types and do not want Malaysian trumpets out competing babies so that is the route I choose. 
 

[nabokovfan87]

On 5/1/2023 at 3:46 AM, Evan said:

If it is, what are my options?

This is a great resource and has the techniques in there to care for the air pockets.

Please let us know if that helps!

If it's easy to do so, the best thing is to move the fish tj a bucket with an air stone and siphon the tank as well as disturb it to release all the bubbles.  Whenever you release them just make sure there isn't any fish above that area.