Hi I am looking for a black substrate that will be good for corys, but also as I am changing my substrate I figured it would be worth me putting down some plant substrate as well. The combination I am thinking of to try and achieve the right look, with the right results, (and the right price!) is using JBL AquaBasis as a base layer, and then capping that off with the Black Roman gravel, as that seems to have a small grain size. Would this be ok? Other possibly relevant info: Current substrate is largish gravel, with JBL clay balls push in around roots of main plants Dosing watercolumn to EI daily with KH2PO4, NO3, and Trace (all from AE) 2 x 39W T5 Lighting Tubes with reflectors 300L Aquarium, (120 x 46 x 70cm (L x W x H) ) No CO2 Injection (I believe with my light levels I am on the border of needing / not-needing it?), but soon to start dosing with EasyCarbo Plants: Ambulia, Cabomba, Java Fern, Java Moss, Twisted Vallis (melting ), Amazon Swords, Flame Moss, Glossostigma (although I think that has died and vanished into the gravel). Soon to add Riccia, maybe hair-grass for a carpet area. Fish load is light at the moment, 5 corys, 8 dwarf Rainbows, but soon to increase to a higher stocking, likely around 30 ish small fish in total. Also if anyone can say why my twisted Vallis would be melting away I'd be grateful Thanks !