Cas wrote:
Thanks David I seem to doing the right thing by the plant .I bought it at
BQ for £10 .Will it be ok to feed it on baby bio?

In this instance yes. It is not really good enough for more vigorous
plants, but will be fine for the Calathea. Not anywhere near as good
as Maxicrop though.

I also have a Dieffenbachia of similar proportions which is doing well. I
placed them ether side of the T/V which gives a good view to any tropical
rainforest program I may be watching.

Dieffenbachias have thicker leaves than your Calathea and as a result
are rather more tolerant of dry air. Depending upon the type of TV
you've got, there will be a fair amount of warm dry air coming out of
the back, which will not be to the liking of the Calathea with its
thin-textured leaves. Conventional (tube) TVs pump out quite a lot of
hot air as do some plasmas and even your precautionary water reservoir
below the plant will not be sufficient to counteract this in the long
run. LCD sets run coolest, but I would not keep any humidity-loving
plants too close to any of them.