# Sand for corydoras, what type?



## Dan-CR4

need some advice on sand as a substrate. I want to get some corydoras and read they should have a sand substrate, but dont want play sand as have also read that it compacts too much very quickly .and can hold gases in pockets of sand. 

so anyone recommend some light coloured sand that will do the job.


----------



## three-fingers

I use play sand for corydoras, as it is inert (made of silica) and very fine (best for their whiskers).

The "pockets of gas" thing simply isn't a real issue IMO.  If you have healthy plant roots, anaerobic (no oxygen) pockets probably wont form anywhere in the substrate.

Plant roots oxygenate the substrate. If you have very deep sand and no plant roots, then if left undisturbed anaerobic pockets would certainly form in the sand.  This would happen regardless of what substrate you used, and could happen faster if you included any organic material or used a special planting substrate instead of play sand.

If you decided to go for a very deep play sand substrate for some reason, any potential pockets of gas would cause _no harm whatsoever_. The aerobic conditions in the sand would actually help clean the water as anaerobic bacteria can consume nitrate. Many aquarists (especially marine) actually WANT a deep sand bed with gas pockets for this reason. Just Google "deep sand bed".

If an anaerobic pocket of gas is disturbed...it will simply float to the surface and cause no issues.  Some people claim the gasses are toxic - they instantly become detoxified upon contact with oxygen in healthy aquarium water though, so unless your fish are already dying and gasping for hair there is no risk.  On top of this...it would be pretty hard to disturb any anaerobic gas pocket as they only form in the deepest areas of the sand which are least disturbed.  You would need to be digging right to the bottom of the substrate and it is obviously hard to do this accidentally with deep sand.

The only other option for a courser sand than play sand would be "pool filter sand". This is more expensive to buy in small amounts, harder to source and not as good for corydoras.

Just go for play sand .


----------



## PARAGUAY

I have read articles using playsand for corydoras ,were depth is  required a base of pebbles or cobbles are used to achieve this.I have a group of bronze Corey's for several years the tank they are in as a Pets At Home sand ,darker more orangey than playsand but never seems to get dirty,it's advertised as a gravel on the packaging a bit misleading.


----------



## KipperSarnie

I use swimming pool filter sand & my Corydoras Sterbai are fine with good long barbels. 
Every night at sunset they all line up in the front of the tank.


----------



## zozo

Or take a peek at the petshops terrarium section for Lizard tank substrates (sand). Try to find one selling Karlie Flamingo products.
Karlie has several sand types in the product line, also aquarium sand, but the terrarium sand is much finer.
http://www.flamingo.be/CatalogusLis...83331ID975348XML0Prod14666256&Page=1&CatMem=1


----------



## sciencefiction

They sell slightly larger sand than play sand in pet shops here, about the 0.6-0.9 mm range.I know one won't be able to measure the grains, but if its not written on the packet then the way to recognise it is if you can easily make out the grains by looking at it but its small enough to look like normal sand. Corys do well in this type of sand are still able to sift through. 

I had to take a tank down that was several years old with this type of sand. I had never disturbed the sand before. When I was scooping it out, it smelled healthy all around, not one anaerobic pocket....Previously had I set up a tank with soil capped with fine sand. After about 6 months when my corys barbels started disappearing, I took the substrate out. It stunk of hydrogen sulphate. The problem there was both the type of sand and the organic layer of soil underneath that seemed not to be getting any oxygen due to the fine sand. The sand was black volcanic sand and although fine, it seemed sharp and the corys did not act on it as if was sand. They never sifted through it.....

At the same time I've been keeping soil capped with play sand for nearly a year now, with corydoras in it and I haven't had any issues. The difference is though that the corys are able to sift through that sand. But between the corys digging and my filters blowing the sand, a lot of soil got uncovered at some stage and it was a mess at the start..... probably helping the sand and soil getting oxygenated too....I would not cap a big tank with external filters with play sand...and I'd keep pre-filters on the intakes as it will get sucked up and damage the hardware.


----------



## Dan-CR4

thanks for all your replies. After going back and forth in my mind if to get playsand or not. I decided to get some Hugo Kamishi sand, saw some in a local garden centres aquatic department and thought, just get that. so now got to empty my tank of water gravel and wood, and start again.  

anyone used this sand? does it need washing through like play sand or just use as is?


----------

