Fluval Stratum as dirt cap?

Fluval Stratum wouldn't be a good cap choice for a few reasons, one being it isn't heavy enough to actually cap dirt as it would eventually let some of the dirt to escape into the water column, another reason is I've used it in the past and didn't like the results it had on my plants. I would go with either pool filter sand or play sand from HomeDepot as a cap for a dirt tank. You could also use eco-complete, flourite, or even regular gravel as a cap for dirt.

A quality dirted planted aquarium will benefit the plants better than Fluval Stratum ever would, I've had nothing but success with dirted tanks in the past, and would go that route again in the future.
 
It depends on what kind of look your going for. If you like the look of sand or gravel, that is what I would cap it with. I have done a dirt tank before, and used gravel for the cap. I personally don't see the point in capping dirt with a plant substrate. Kind of defeats the purpose of the dirt doesn't it? But if that's what you want to do, I have no experience with Fluval Stratum, so can't really comment on if it would work or not. Eco Complete would.
 
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