# Capping Safe-T-Sorb Substrate?



## goodbytes (Aug 18, 2014)

I'm starting a new tank--making the jump to medium lighting--and I'd like a good, inexpensive, and relatively easy to find substrate. The high CEC of Safe-T-Sorb seems ideal for this project and it fits the aforementioned criteria. There are apparently some problems with it though--its dirty, troublesome to plant in because its too light, and can break down overtime. Could this be solved by capping it with some black blasting sand? Will the desirable high CEC be nullified in any way by capping it with sand?


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## Seattle_Aquarist (Jun 15, 2008)

Hi goodbytes,

Safe-t-Sorb #7341 is 'dusty' and the first wash is time consuming. As for the weight, I would rate it about the same weight as ADA Aquasoil. You can cap it, it will not effect the CEC of the STS other than you will have less STS in the tank. If you cap it with sand, or with Black Diamond Blasting Grit it is likely that the smaller particles of the sand/grit will settle to the bottom and the STS will start showing on the top. Maybe someone else who has capped this substrate will chime in, I just use straight STS in my tanks.

10 gallon with STS #7341


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## goodbytes (Aug 18, 2014)

Makes sense. Have you ever had it turn into mush on you?


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## Seattle_Aquarist (Jun 15, 2008)

Hi goodbytes,

I have used various calcined clay products for about five years including Soilmaster Select, Turface Pro League, and STS #7341 and have not had any deterioration at all........wish I could say the same about ADA Aquasoil.


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## WaterLife (Jul 1, 2015)

Depending how thick of a cap (or how tightly the cap compacts), I would imagine it would hinder the STS ability to absorb more nutrients from the water column due to less contact with the water column. Though as long as the cap is only a inch or so thick, the STS should still be pretty effective (enough water should still be able to penetrate down to the STS layer).

I've never capped any substrate, but I have heard that smaller grains will eventually sink below the larger substrate (sand would work it's way under the larger STS), but I think that takes quite a long time. Can't speak from personal experience though.


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