Things are coming along with equipping of the 275l discus tank. I should point out that this is an established tank that's been running for 18 months, but I had to strip out all the plants, decoration and substrate as I acquired leeches from somewhere. Luckily, having spent 3 months as a bare bottomed tank, I have not seen sight of a slimy critter for 7 weeks. Anyway, the new substrate is now in, and I have 2 - 3 inches of carib-sea eco-complete in the tank. What I want to ask is this: As I replant the tank (pretty heavily) with an FE CO2 system, when should I start dosing the water with ferts? Presumably with new eco-complete, I don't need to dose for a few weeks or months? How long would people recommend before dosing, and what product would people recommend? I keep reading multiple threads involving TPN+ and Easycarbo and EI and I can't decide what might be the best way to go! Thanks in advance for any info people can provide / suggest.