Growing Melons in my Flow Through Worm Bin

I've been eating a lot of melons lately since my worms like the rinds.  So now I have more than enough seeds than I'm prepared to deal with.  So a lot of times, I just throw the seeds in with the rinds inside my worm bins.  In my flow through try, I've had dozens of melon seedlings sprouting at the same time.  Since the contents of the bin are almost fully processed anyway, I figured I would just grow the melons.   As you can see though, the tray is quite shallow.  So how can I grow big melon plants from here?  For one, I'm using pure vermicompost so I'm hoping the roots get their nourishment without a problem.  The tray also has holes in the bottom.  You can't see it very clearly, but there's a covered aquarium underneath.  If roots grow through the tray, they can anchor inside the aquarium.  The aquarium is filled with paper and coffee grounds and of course a couple of worms.  You get the idea, right?  In a month or so, I'll see if it works.  But what happened to the worms?  They're still there.  However, I made the materials in the aquarium high enough so that they touch the bottom of the tray.  The tray gets some sunshine so if it gets too hot, the worms can crawl down the aquarium.  So far, the worms are alive.  My problem though is that the contents of the tray keep dipping since worms tend to poop underneath the tray.  To help keep the tray contents up, I just add shredded paper and coffee grounds regularly.   Once the melon plants grow bigger, I'll tie a couple of straws from the gate to the tray for that trellis effect.  Watch out for it!   

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