Ok thanks, I got fluorite by seachem and thrive as a fertilizer, I'll try again, thanksWater sprite is like spreads like a disease in my big tank planted in sand with no fertilizer, but a heavy bio load. I have nano tanks with light bio loads and nutrient enriched substrate that I have to add fertilizer to, and l have dwarf hair grass growing. I’d say that if your using a decent led and you can’t get plants to grow then you are probably missing something. It could be you don’t have enough plant food, or your not providing enough light, or your temperature is to high or low.