My Sand keeps bubbling

[Jen]

I just set up a sand tank, with a layer of small gravel underneath for airholes for plants to grow. I have put in air stones and thats pretty it.

Since then, there are these spots where all these bubbles come up out of nowhere. Is this my sand still settleing or is the air from the airstones travelling under the sand and just finding an escape?

 

[impur]

Probably just excess air escaping from the layer of gravel. How thick is the layer of gravel compared to the sand? The reason i ask is that the sand will make its way down to the bottom of the tank. Think of a bag of potato chips. The larger ones are always on top, the crushed pieces fall to the bottom.

 

[utahfish]

the air stones are probaly pushing the air through the sand. what do you need the air stones for anyway?

 

[Jen]

Probably just excess air escaping from the layer of gravel. How thick is the layer of gravel compared to the sand?

That's kinda what I was thinking. The gravel is about 1/5 the sand. Not much at all. Just enought for roots to spread, I think.

what do you need the air stones for anyway?

The air stones are to add oxygen to the water for the fish, and to help keep the surface water moving

 

[fishdudein]

Hi canoechiq! I would agree that it is probably excess air escaping. However, if the tank had been set up for awhile, it could be nitrogen bubbles. I know this works in saltwater, I would assume it would work in fresh also. If the sandbed is deep enough, you get a colony of anaerobic bacteria (don't require oxygen) established in the sand. Rather than the ammonia going through the conventional nitrogen cycle where it is converted to nitrItes then to nitrAtes, the anaerobic bacteria convert it to nitrogen gas, which bubbles up through the sandbed and is released into the atmosphere. Works well in conjunction with the nitrogen cycle. Don't know if this is any help for you, but maybe food for thought.

 

[Jen]

The tank is a born again tank... set up for a mere 4 days, so i'm thinking its not the nitrogen thing...

but thats good to know

 

[Max]

the air stones are probaly pushing the air through the sand. what do you need the air stones for anyway?

somtimes people use airstones for looks... my cusin does that, personaly i only use then for co2 injections, and for my dragonfish tank because i dont wana use a hang on filter (its weird.... but to make a long storie short he needs more air then other fish...)

 

[Lateral Line]

In a normal tank, airstones are quite un-necessary, the filter will move the surface around enough. If you like them, fine, that's different. I haven't used one for years.

Mixing sand and gravel, (and other "layered" substrates), will, as in the bag of chips analogy, simply sort itself out with the actions of the fish, plant roots and maintenance activities. If you added the gravel to assist plants - this is not necessary. Most plants come from very fine silty substrates - mud basically.

Anaerobic bacteria in a freshwater tank is undesirable. You should keep your substrate open to avoid it. It generates Hydrogen Sulphide which a) stinks and B) is toxic.

 

[Jen]

You should keep your substrate open to avoid it.

What do you mean by that... and how do I do it?