Backyard Aquaponics
A place to discuss aquaponics

Ok so I posted this in member systems but I thought I'd post this here too.

The 2 plants are grown in pretty much the same conditions but one had more light in the first 3 weeks of growth. The one growing properly had more light. I also just read something that said water level (even very minute differences) may cause some problems. I'll have to look into that.

Any ideas why one is growing like a tree and one isn't?

Usually it means lack of light or nitrogen.

A bit of both for sure, even the good one does not look fully green.

More light, and some maxicrop / seasol will do the trick. As long as the water is around 1" below the surface of the media it is ok.

I'd give it more light. 30-50 watts per square foot is optimal for indoor gardening. If after increasing the light still no improvement I'd feed more to the fish. Also, you could have a virus or some type of nematode. Can't really tell unless you have a control group or do a couple of harvests.