[aquabillpers]

Indeed, the use of Equilibrium in 'El Natural' aquariums may not be problematic if the soil underlayer is mostly aerobic.

snip

If your aquarium has abundant plant growth with robust root penetration throughout the soil, sufficient water circulation, and a soil layer that is not too deep or too dense, then the use of Equilibrium may pose no problem at all.

Thanks for the explanation!

Unless I'm missing something, it would then seem that planted tanks that are set up under Diana's guidelines would tend to have aerobic substrates, at least those that did not use dense soils. Right?

I also don't know how much sulfate would be too much. There are numerous substances in nature that we ingest in small quantities every day without causing us difficulties; the same substances taken in larger quantities would be fatal. I wonder if there is enough in Equilibrium to cause a problem.

Thanks again.

Bill