My fine river sand bubbling and float

[Shadow]

not sure where I should post this question.

What happen is my fine river sand substrates are pearling and float during photo period

My theory is algae grow on the sand surface and during photo period it produce O2 and float. Problem is, it raise, once reach the surface the air bubble pop-up and the sand sink back all over the place carried by water flow. It dirty my plants.

Any suggestion on how to clean it without sucking the whole sand and replace with new one?

[Jungle-mania]

It could also be an overproduction of aerobic bacteria growing in your substrate, is there a smell of methane coming out of the tank? My advice is to wash your sand and put it back to ensure there is no problem. Even if it is algae growing in your sand, it will eventually decompose and you might get nitrate spike.

[Shadow]

no stink smell, unless my nose block

I'm hoping there is other way beside suck all the sand and replace it with new one or soak it with H2O2.

[Shaihulud]

I don't know anything much, but isn't algae ubiquitous? By that i mean even should you sterilize the sand, they will make a comeback. Sand is pretty heavy, it has got to be pretty much algae coated to produce enough oxygen bubble to cause sand to float.

[Shadow]

This is fine river sand, it is very light.

it will come back but it will take a while, hopefully.

[eddyq]

I don't think fine sand can float even they are very fine. If possible replace them with another type.

[Shadow]

My theory is algae covering the surface of the fine sand, and during the light-on, it generate O2 and it float. I said this because it is only float during light on. The only way to clean it is such every thing and pour H2O2

[luenny]

Hmmm ... could be anerobic. Try stirring it with your tweezers and see if the bottom layer is black?

[Shadow]

nope, only the surface that float the rest is ok.

[hebi]

i have the same problem too before i introduce my cherry shrimps. once in a while i will notice a bubble float up then burst, then a grain of sand drop down. then i realise is the sand area below my dw is turning brown? i never feed alot to my guppies that i use for cycling and ensure no leftovers. then at the side on the tank , the sand are covered with green algae. but then i think no problem since they photosynthesize too and can serve as food for the cherry shrimps. anyway, i can see many pockets of air bubbles trapped under the sand and some part of the sand are turning green.

[Shadow]

too bad I had pair of apisto at that tank. I did try to put couples of yamato, but it was attack and killed by apisto .

[taygu]

Will vacuuming the sand help?

[Shadow]

It is too fine and light so vacuuming will also suck the sand. It does help but you need to top up after that. What I did is vacuum it, pour H2O2 in to the vacuumed fine sand, wait few hours, rinse it and put back into the tank.