Although my japanese hairgrass is growing really well (sprouting all over the side) they are very very yellow. Whereas for my mc, the growth looks stunted and the leaves all yellow yellow too with some having dark patches (this time round not the dirt).

I read that i need fertilisers like iron, potassium and maybe phosphorus. Managed to find ferts for potassium n phosphorus. But for those iron ferts, it contain quite a high percentage of copper (bad for my shrimps) too. Anyone know of any ferts for iron that doesnt come with copper?

Thanks!