Only Plants, No Fish

[fishstick]

I have a spare Hex 60l tank in which I would like to grow only plants. I know I would have to put in a rich substrate under some sand and provide heat and perhaps CO2. My question is this: does a tank with no fish in it but full of plants need biological filtration or just the water pumped round?

 

[qwikimpss]

All you would need for a plant only tank would be some water movement, a good substrate, lighting and ferts (which are especially important since there are no fish to make wastes).

Plant-only tank....sounds a bit boring to me (IMHO) but to each his own.