I need to know what fertilizers or chemicals are needed for my plants. I'm using flourite and pool filter sand as substrate, no co2. sword plants mostly
You may need no fertilizers at all. Without injecting CO2 your demand will be low (there are so many factors in determing whether or not you do need fertilizers that I would need to write a long article decriibng even some of them). If you do decide to fertilize I would start at once a week with something like PMDD Pre-Mix from here:
http://www.aquariumfertilizer.com/st...cplantfood.php
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