Anaerobic sand?

[Dd10]

Hi there,

I have fairly deep sand in my tank, and this has developed some black layers. I'm concerned about this being anaerobic pockets, and I'm not sure what to do. Is it better to leave it be or do something to solve the issue? Tank has been set up for just over 4 years

(The black gravel is eco complete which was used at the sides of the tank but has mixed through slightly)

Any advice appreciated!

 

[Boundava]

Well two options (3 of you feel you need to)

1. Don't disturb the sand bed, any possible pockets of noxious gasses are currently trapped.
2. Get a substrate dwelling invert like (GULP) Malaysian trumpet snails. They do a great job burrowing in and cleaning up substrate. So long as you don't overfeed their population should remain in check.

3. Break down the tank (remove fish/decor/plants and either remove/replace the substrate or do a deep and thorough substrate cleaning to get any anaerobic pockets in the substrate and possibly remove some of it so it's not so deep (or do above, leave same amount and add the snails).

 

[Dd10]

Well two options (3 of you feel you need to)

1. Don't disturb the sand bed, any possible pockets of noxious gasses are currently trapped.
2. Get a substrate dwelling invert like (GULP) Malaysian trumpet snails. They do a great job burrowing in and cleaning up substrate. So long as you don't overfeed their population should remain in check.

3. Break down the tank (remove fish/decor/plants and either remove/replace the substrate or do a deep and thorough substrate cleaning to get any anaerobic pockets in the substrate and possibly remove some of it so it's not so deep (or do above, leave same amount and add the snails).

Thanks for the advice. I'd really rather avoid breaking down the tank. If I add trumpet snails should I be concerned about the noxious gasses being released by their burrowing? I'll definitely avoid disturbing the sand in the mean time regardless

 

[Byron]

What is along the front glass is likely to be algae more than hydrogen sulfide. Definitely do not disturb the sand anywhere unless you remove all fish first. The depth is quite a lot, and anaerobic patches are part of a healthy substrate, but not to excess. No way of telling what the entire substrate is like.

 

[Dd10]

What is along the front glass is likely to be algae more than hydrogen sulfide. Definitely do not disturb the sand anywhere unless you remove all fish first. The depth is quite a lot, and anaerobic patches are part of a healthy substrate, but not to excess. No way of telling what the entire substrate is like.

Thanks, I'll avoid disturbing it - I'm just concerned as the black areas are quite close to the surface. I'm assuming I would smell it if it had been disturbed though

 

[Colin_T]

Yes it's anaerobic.

You can use a gravel cleaner and push it into the sand and leave it there for a few seconds so any bubbles come out and go up the syphon hose. That will stop them getting into the water. After a few seconds, lift the gravel cleaner up and move it to another spot and push it into the sand. Repeat until you have drained 50% of the tank water. Top up tank with dechlorinated water. Next time you do a water change, do another section and so on until the substrate is clean.

If you kink the syphon hose a bit, it will slow the water flow and you won't suck the sand out.