Echinodorus 'Ozelot' Maintenance

[presto]

I have a Echinodorus 'Ozelot' plant I got from a friend and I am looking for advice on it's care.

The plant is very large and the following has happened:
1) black algae on leaf tips,
2) thinning of middle section and tips of some leaves(like soaked paper towel, dissolves when touched)
3) new red leaves growing from center of plant(older leaves are green)
4) It is taking over my tank

I have recently removed all the thinned leaves and peeled other leaves from the outside inward to reduce the overall size. Is this right?

I have 2.5 wpg, co2(DIY) and I dose the tank with dry ferts using EI but the plant doesn't seem to be doing all that well even though it is growing. The thin leaves concern me. Is there special care this plant needs?

Thanks

[charlie]

Sword plants take their nutrients mainly from the substrate through it`s root system as a result it is a good idea to put a root tab in the substrate under the plant, my preference is the seachem root tab but their are others out there.
Regards

[presto]

Thanks Charlie,
I will try Seachem tabs.