need float valve

I have a 1/4 inch but I would recommend getting 3/8" (which is why I have 1/4" laying around, I switched.)
Great prices here:

 

Careful doing that man, just be sure you keep an eye on it, if it sticks you are going to have a serious flood could wipe out your entire tank. I used to top off like that and only had it stick a couple times. You would be better off putting float valve in a resivour that holds your top-off water and then use a small pump like an aqualifter on a float switch. Just so ya know, doing what you plan on doing is risky...

 

I agree Jeremy, but your float switch can stick as well. I am very diligent about every week taking out the float and cleaning it. Have not had a sticking open problem in two years with proper maintenance. I have the pump as well and control it with my controller but it feeds the float so I maintain a constant level. That way it should not overfill too much if there is a problem. I have three lines feeding this one 3/8 float valve. RO/DI, Kalk and Salt water all with separate pumps controlled with my AC3. The salt water line is for automatic water changes.
I am not disagreeing but saying overflows can be avoided with proper maintenance. There are many things like that is this hobby as we all know. At present time I am a huge fan of these float valves from US Plastics. My biggest problem was the 1/4 clogging with kalk, so I upgraded to 3/8 and that seems to be solved.

 

True, the float switch can stick, but its not hooked up to an endless supply of RO water...

Joel, sounds like a cool setup you have, i though about doing something like that but being i have a CA reactor i just top off with kalk only.
I would be interested in hearing about your automatic WC setup as well.

Sorry about your thread Troy.

LOL

 

I had a hard time understanding how yours is setup Joel, but it sounds like you are monitoring it with your aqua controller as a precaution?

I agree with Jeremy about hooking it up directly to the sump...bad idea even if you do clean it often. UNI's tank is setup this way and it floods all the time. One of the times was because the float switch (bulb) had a crack in the seam and it would fill up with water and not have enough strength to seal the connection.... How'd it get the crack? Who knows, just a manufacturers quality defect I guess. Besides its much easier not having to clean it!

The way mine is setup now, is a trashcan reservoir hooked up to my RO with a float valve that turns off the RO when it is full. I fill the reservoir about every 2.5 weeks and then turn off the RO so it doesn't turn on and off constantly throughout the week. I have a autotopoff.com double float switch in my sump fed by an aqualifter that pulls RO from the reservoir. Both float switches in the sump would have to fail in order to flood the tank. Perhaps the reservoir could flood, but if it did, it would only flood the floor and not the tank.

 

Taavis, There are lots of ways to do it. I agree Waverz on the reservoir, thats the best way to go IMO. I use an old 10g tank that feeds the sump by gravity and controlled by 2 electric solenoid valves.

I use 2 electric solenoid valves on mine, encase one sticks. plus my sump holds more then the 8g that I put in the reservoir.
My whole top off system is on a timer that turns on a little bit before the time I feed my corals every night, that way if theres a problem I'm right there.    

 

Autotopoff.com has float switches with the controllers built right it, all you need is an aqualifter and a small resevoir with a float valve and your set. I also have a solenoid valve in my RODI feed line, it's on a timer and is only open when i am home, so if there is ever a problem i will be here to catch it.

 

We have so many things in our setups that can go bad Lee. A bad float is definitely a possibility. But look at the many ways people have catastrophes like tank crashes - Heater, tank seems, GFI or circuit outages, bad pump and on and on. Something can always go wrong - our own fault or equipment goes bad. With good maintenance this setup can work very well. I agree that feeding the sump with gravity adds another place for things to go wrong. Nothing I have is gravity fed. Clean these floats once a week and replace every one to two years. That is my schedule and I keep it on a computerized calendar (someday will be built into Reef Trakker /DesktopModules/ActiveForums/themes/_default/emoticons/biggrin.gif).
The auto water changes are actually pretty easy with a controller and a float valve. /DesktopModules/ActiveForums/themes/_default/emoticons/cool.gif/DesktopModules/ActiveForums/themes/_default/emoticons/cool.gif
I have a double 90 of 1/2 PVC over the edge of one of my tanks that leads to my drain. Attached to this is a MJ1200 with 1/2 inch tubing inserted into the 1/2 PVC going over the edge. I have cut holes in the top of the tubing to keep from creating a siphon. My controller turns on the MJ twice a day for one minute. This is metered to empty 1-1/2 gallons. So I drain 3 gallons a day. I used to have an electric solenoid on this but it would stick and siphon out too much.
Then I have a pump in my salt water reservoir that is controlled to turn on for 10 minutes twice a day just after the water has drained. This of course leads to my 3/8 float valve to keep the sump at a constant level. This has worked VERY well now for about six months.
My business is writing Maintenance Management software professionally. I deal with over 500 maintenance departments. Our software sets up schedules to regularly maintain equipment (plus much much more). If something has a bad design it is going to fail you are correct. Usually the more complex the more chance for failure. But if equipment is maintained well it can function well for a long time, many times longer than if it is not. Not to mention it saves big $$$.
People in this hobby are so afraid of float valves because many have had failures, I think there may be some very bad floats out there as well. The one I suggested is a very good float valve if maintained. I am saying if you are like I am in many aspects of my life and don't maintain things they will break down. I just blew the engine in my tractor, my fault, I hadn't maintained it like I should have been and spun some bearings. But my tanks are maintained daily, and weekly I use a check list. I am telling you /DesktopModules/ActiveForums/themes/_default/emoticons/hehe.gif this system works well if Maintained. Don't be afraid of it unless you know you won't maintain it.
Phrase of the day .... can you guess ...... "proper maintenance" /DesktopModules/ActiveForums/themes/_default/emoticons/tongue2.gif