Hmmm... I'm assuming that with the stock in there aquatic plants don't last very long... Gunner has a cool idea of using hydrophonics to keep the nitrates out of the water. I'm not sure how you tank is set up but he attaches the plants so that the roots are in the water flow out of the filter. I suppose for your case that may or may not be something that you're fish would tolerate. If you have the skills or could find the following this may be a way to accomidate them:
1) attach a wide dimesion pipe (black plumbing) to the back of the tank and put the output hose of the canister in one end. at the other end have something that would dump the water back into the tank. Suspend the plant roots in the water and watch grow (no dirt required).
2) Place a shelf on the wall just slightly above the tank. Build a glass box and drill the bottom of one side run pip discretetly down through the shelf and into the tank. Drill a hole just a little above the half way point in the other side (or higher if you wish) the water will enter the box, run over the roots and down the pipe into the tank. Using a vine type plant that would run of the sides of the box and drape down would hide the pipe and hose.
3) attach to the filter as Gunner shows in
this thread... (post 7)
Hope that those idea's help...
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but mine were in a 75 gal
