Hardwater planted tank - substrate

[Sea-agg09]

I'm doing a small tank with hard-water species. I want to have some plants in hard/alkaline water. I need to find a substrate that will not alter the pH of the water. I've heard that eco-complete doesn't drop the pH. Is this true?

[davemonkey]

That is correct. In fact, I have read that it actually can increase hardness (not sure how much...probably not enough to be concerned about unless you already have hard water and want to grow plants more suited to soft water).

[Sea-agg09]

Sulawesi plants come from very hard and very alkaline water. Some/most of the plants are basically calcareous like some saltwater macro-algae. Most people put them in slightly acidic water and watch them dissolve.