Thanks Ness. My java fern used to go like that and from what I have learnt, it's potassium. Since I started with the Aquagreen products, all good.
@Sarah. Thanks. That is HM at the front. It was pretty sick before with bright green tops and the rest was rust coloured. Has really come back now. Yes, that is a male peppermint. :-).
Tank is about to be pulled apart as I want to do a natural tank. My biggest issue is my substrate which had cichlids in mind. It is full of shellgrit so ph is always 7.8 approx.
Hopefully I will do what Shadoh is about to do. I may try a smaller tank first as a trial run. Not sure, depends on my patience.