Building Up 'sand Bank' Aquascape

Hi all,

My 200l aquarium has been running over a year now and after reading PFK magazine and looking online I feel inspired to maybe make a small change to my aquarium.

I am thinking about burying the large drift wood piece (with a lot of care not to damage anything) about 1inch into the sand substrate and then build up a 'sand bank' around the front left and then up the side left between the glass and side of the wood and up the back. From there I plan to plant into the bank. I will be planting plants into the bank that my pesky buenos aires tetras won't eat, probably avoiding vallis which is only left untouched behind the wood at the moment.

Right now for my question .... I have read that if substrate is too deep it can cause an anaerobic buildup of gasses? Is there a method to prevent this? I have seen banks built up using small rounded cobble stones and then topping over with sand. Any thoughts on this?

Thanks, DJT

If you put sand on top of cobbles, you'll find that the sand will tend to work its way down between the cobbles and disappear. You might have to keep topping up with sand until every last bit of space between the cobbles is full of sand. Of course, this will mean that you no longer have air spaces between the cobbles and therefore the risk of going anaerobic returns.
Lots of plants, so that the substrate is filled with their roots, are very useful for reducing this risk.