I still use on one of my sump's the first float valve I ever bought for a tank more than ten years ago. It's been in continuous use as an ATO in the last ten years without a single failure. Best $8 I ever spent in the hobby. I bet most $200 switch and pump style ATO's cannot claim that kind of uptime yet. Sometimes simplicity is just fine.

I also have one on a brute trash can with a ball valve right before it. After a water change I let it fill up to the float valve and then turn off the ball valve as an extra precaution.

I have a friend in town who flooded his basement twice using one of these in much the same way. I dont know the full story about how it happened but I think he just had it mounted too loose or the float wasnt inserted correctly. Water on the floor sensors are always a good idea and check your installation to make sure it works before turning the water on and leaving for the day...

I'm seriously thinking about this for my next sump. But I got 2 FW tanks I use the RO water for too. Maybe when I finally get rid of them? How did you mount? Did you drill through sump? I'd like to be able to add it after. Glass sump, don;t want to remove to add a hole

living on the edge here.

I have a furnace humidifier float valve in my sump connected directly to my ro/di for a ATO for the last 4-5 years, zero problems.

What let's me sleep is there's many more furnaces out there than fish tanks and in all my years never come across it myself or heard from someone their basement flooded due the humidifier. I've had a problem once on a old furnace with the valve not opening from deposits. Figure here I'm running about 2g a day of ro/di through it, it's flushing itself.

Now would not use one on a kalk drip system.

http://i67.photobucket.com/albums/h316/das75/float.jpg

That's the one. Yeah i just drilled a hole in the can. So based on everyone's experience I think I'll be good :)

Glad I heard about this. Really great item

Yeah, just a 1/2" hole through the glass and done. I'm liking Mark's slotted idea in the corner of the sump for adjustability though - probably pretty easy to set up with some acrylic and a router or worst case scenario some glass slats siliconed together (I don't have a router so just thinking out loud how I'd go about doing it myself..)

Mark, I don't know how you're not burning through RO membranes like that.. but hey, if it works, it works. I myself found out the hard way to use a reservoir first .. but we all know the laws of physics are totally different up there in E-town than down here so that must be it.

Well I guess some of you guys enjoy living on the edge a little :lol:. Even with an old humidifier without an overflow drain, if failure occurs it still spills down close to a floor drain so no damage is done. Also keep in mind that a fish tanks isn't exactly the same as a humidifier. In the tank environment it's much more vulnerable since it isn't as clean and things can jam it up or stop it from closing.

Simplicity is better as a rule of thumb within reason (a car is still better than a horse) but mechanical floats do fail so I think it'd be pretty foolish to hook up one to an actual aquarium from an unlimited water source, if you've got a separate container for top off which wouldn't harm the tank if it was all introduced that's fine but a direct RO hook up is an accident waiting to happen. A solenoid and a timer can be easily setup for less than $100 which is very cheap insurance considering what has already been invested.

True dat Steve, the most sage outlook is to assume anything can fail - valve or switch or whatever, and then plan accordingly in anticipation of the what-if's.

I'm not sure a horse is simpler than a car though. I'm a city boy with a wrench, I wouldn't know the first thing to do with a horse but I can tinker in an engine. So to some extent "simpler" might be a matter of perception. :p

How do you adjust it? Wouldn't water flow out the slot if you move it up?

The one drawback about how I do it is if I drill the hole in the wrong spot then I'm stuck with a hole I either have to live with or patch, and either way sucks. The hole needs to be about 1.5" (maybe more, I can't remember for sure offhand) above where you want your waterline. So a slotted attachment point instead of a hole allows you to position the valve where you want it, as long as you can still attach it solidly (ie., any wiggling would be "bad"). And then if you want more water or less water in your sump you can adjust the valve to a new position and retighten, rather than drill a new hole.

But the slot then has to be IN the sump of course, and not the tank wall.