moneywort melting

I've had problems with moneywort in the past and only recently began using it again...I think it can be a beautiful plant. That said, IMO it really needs hight light to sustain growth and an excellent condition combined with pressurized CO2. It will eventually grow water roots to absorb nutrients. And I have only recently noticed this phenomenon. Thus additional ferts will help, but only after its begun to show signs of growth initially. As for the temp. my tank is usually room temp 70 degrees so it is possible that raising the tank temp could inhibit its growth. In the past the melt off that I experienced was due to insufficient intensity and quantity of light / CO2 concentration...