Installing flood and drain pieces on table (how?)

I have a 4'x6' Canadian Ebb And Flow tray and was wondering what the best way to install flood and drain pieces is? I have already drilled the two holes using a 1.25" spade bit. The flood and drain pieces both fit well but there is just enough room between the pieces and the table in the hole for water to leak through. Is there any sealant that would work well or any methods that are tried and true? Any suggestions are most welcome. Also, what can I do to stableize the flood and drain pieces more? They seem flimsy in the holes.

silicone caulking? There is this stuff called automotive goop that works. I used it to fill a crack on my house plumbing.

caulking is best

Silicon caulk seems too flimsy to me. Could I use a hard drying caulk that would repel water and keep the flood and drain pieces in place better?

your suppose to use a ebbnflow fitting with a screen.

like this

Hydroempire, Organic Hydroponic Nutrients, Indoor Grow Lights and Supplies - Fill Fitting w/ Screen [HSPM-FDF] - $3.95

Plumbers putty. Available anywhere they sell plumbing parts. About $2.00 for a lifetime supply. Not that I recommend it, just sounds like you would be more comfortable with it. The fittings I bough came with a washer that works just fine. The fittings aren't structural parts, they don't hold up anything. VV

I used aquarium sealant on a system that I built with a buddy a few years back, and still holds water to this day, we figured if it was safe for the fish that it wouldnt harm the plants either...http://www.dap.com/images/products/hires/aquarium28ozBlisterCard.jpg