I have a well stocked year old 125l tank with just sand substrate and 15 recently added plants which are a mix of crypts, java fern, anubias, swords, rotalia, cabomba and ludwigia peruviana. Lights are 2 X 20watt t8 and 1 Arcadia stretch 24watt led. I'm adding JBL ferropol weekly and 2 ml...