I have an aquaponics setup in a 5 gallon aquarium. Ivory been using leaf zone aquarium plant food to add iron and potassium to the water to get rid of the leaf yellowing problem I wad having. Everything was going good for a couple weeks but now the tips of my leaves are wrinkleing up and starting to yellow a bit. The rest of the leaf looks great its only the very tips. Any advice would be greatly appreciated. Would put pic but can't figure out how offbof cell phone.