Safe-T-Sorb

Also sold as Safe T Sorb · STS · oil-dri · oil dry · floor dry · calcined clay · SafeTSorb · EP Minerals 7941 · Safe-T-Sorb (EP Minerals #7941)

Safe-T-Sorb from EP Minerals is an inert clay or lava gravel. It holds no nutrients of its own, which is what decides whether it suits your plants and your shrimp.

At a glance

TypeInert clay or lava gravel
NutrientsNone (inert)
GrainMedium
BrandEP Minerals (generic oil absorbent)
Effect on pHNeutral
Ammonia when newNone
ShrimpSuits Neocaridina

Before it goes in

  • Safe-T-Sorb is an inert clay or lava gravel.
  • It is inert: it holds no nutrients of its own. Root feeders such as Cryptocoryne wendtii and Dwarf Hairgrass Mini need root tabs under them.
  • It is pH-neutral: whatever comes out of your tap is what the tank sits at.
  • It releases no ammonia, so livestock can go in as soon as the tank is cycled.
  • It is rough on fish that sift the substrate. Something finer suits German Blue Ram and Julii Cory better.
  • It suits Neocaridina, which want harder water than Caridina do.

What kind of substrate is it?

Inert clay or lava gravel, medium grain, holding no nutrients of its own.

Does it change pH?

No — it is inert and leaves your tap water where it is.

Does it leach ammonia?

No, so you are not waiting on it to stop before stocking.

Can I use it on its own?

Yes — Safe-T-Sorb is a complete substrate on its own.

What it goes with

Often compared with

Safe-T-SorbTurface MVPSeachem Flourite
TypeInert clay or lava gravelInert clay or lava gravelInert clay or lava gravel
NutrientsNoneNoneSome
pHNeutralNeutralNeutral
GrainMedium0.9–3.4 mm3–8 mm
Leaches ammoniaNoNoNo

More substrates

Sources (5) · checked Sep 2026