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[Delphinus]

Yeah those humidifer float valves work quite well. Both Jon & I use them on our setups. I never modified mine though, even with the tiny hole it works fine. I just use a 5gal. bucket for my freshwater reservoir.

I've used eggcrate for mounting, an acrylic divider for mounting, and, I've also made a tower using 3" PVC, and a toilet flange for a base. Only problem with this tower is it needs to be held down otherwise it kind of floats around a bit.

BTW, NEVER put an infinite water supply on a sump topup though, that is playing with fire and gasoline.

Another trick you can use instead of the 1/4" bushing, is, at the hydroponics stores you can get what is basically a tiny 1/4" bulkhead with barbed fitting that you can slip an airline tube over. So you just drill a 3/8" hole in the bucket, and use this mini-bulkhead and away you go.

But, if you ever do want to mount a valve into glass, I can help you out there as I have some glass drill bits. Works like a charm.

Fun stuff!