Planted tank question...

My corys thrive on CaribSea Sunset Gold sand, my preferred sand and the only one that Jeremy Basch uses in his fishroom. At least one renowned corydoras breeder uses glacial sand (nicely rounded silica particles due to glacial grinding action) which he purchases by the pallet. I was thinking of having the club sponsor a group buy for a pallet of glacial sand if enough people are interested. It would be very cost effective. I'm not sure what the color is but I assume whitish gray.

My C. adolfo colony is currently being kept on fine gravel (CaribSea Peace River), and they are thriving and their barbels are healthy. But I have to stay on top of siphoning or they will run into trouble. This causes angst because it's a breeding tank, so every time I siphon I probably lose a bunch of larval fish. If I kept them over sand, it wouldn't be as stressful. To clean the sand, Rachel O'Leary recommends taking a chopstick and running it through the sand to kick up detritus into the water column and then siphon that. This technique has been working very well for me in other tanks, like the ones where I keep Morse Code Corys.

But in general, most corys prefer to be on sand and leaf litter (with the notable exception of some of the mountain dwellers which are over large gravel and boulders and enjoy cooler temperatures). It's especially important for long-snouted corys to be on soft sand since they have evolved those long snouts to plunge into a soft substrate. On gravel, they aren't able to exhibit their natural foraging behavior. Short snouted corys are better adapted to living over gravel. Just some more food for thought.

Thanks for the info everyone... I will probably spend the extra $$$ to get a plant friendly substrate that won’t kill my clown loaches...

Hi Folks,

The club geologist here. I would advise anyone selecting a new substrate to view it with a 10X hand lens, a microscope, or some other magnifying device and inspecting it carefully for sharp edges that would harm soft catfish or loach barbels or earth eater gills. For bottom dwellers, 'snufflers' like Corydoras, and earth eaters we should use only substrates with rounded edges. Glacial sand is perfect.

If you look at EcoComplete under magnification, you will see that it is made up of volcanic pumice bits with sharp, broken glass (literally broken volcanic glass) edges. I've used EcoComplete in the past. It's fantastic for planted tanks and fish that don't burrow, sift, or eat substrate. Great for tetras, danios, and any other fish inhabiting the water column. However, it will cut up your Corydoras' barbels and would most likely be fatal to earth eaters or at the very least prevent them from engaging in their normal eating behavior. If you find you're having lots of mouth fungus or barbel erosion problems, look carefully at the substrate.

I've never used blasting sand but suspect it may have sharp edges which would make it effective for blasting. If it does have sharp edges, then the same advice as EcoComplete applies. If not, then it would be good to go as long as the chemistry is appropriate for fish. Certain dark rocks may contain minerals high in nickel, manganese, or other heavy metals which may be fatal to fish or especially invertebrates over time as these elements leach into the water. It all depends on the source rock composition from which the sand was derived.

Cheers, Patchin

We have used some Black Diamond Blasting sand in four tanks -- three 20 gal longs, and a 55 gal. There are two grades of the black sand. We prefer the coarser grade. Medium and large sized fish can sift through it, but it does not have quite as many particulates. You'll want to wash it out in a bucket to get rid of very fine cloudy dust. We also found that capping it with a bag of Eco Complete really helped. In our 55 gal. set up, we used the fine sand on the bottom, then coarse sand above that, and then two bags of eco complete.

I've used it in 3 aquariums ( one is a "dirt tank setup"). The only problem I have with it is the build up of brown algae or diatoms. Probably due to high silica . It is a cheap substrate. It is sold at Tractor supply company which is located right off of Rt 66 in Manassas. Cheap...only $7.99 per 50 lbs. I believe it is an inert coal by product.

Thanks Matt!

I haven't, but there are many posts about it at the Planted Tank Forum: https://www.plantedtank.net/forums/gtsearch.php?q=black%20diamond