Resevoirless auto top off?

[rob020880]

So I am trying to figure out how best to setup a resevoirless auto top off system that connects my ro\di directly to my sump. I have gone over this in past threads and I know that it is not the best idea in the world, and that something is bound to go wrong. But what I have learned in my research is that if this is to be done redundancy is key. So I will double up or even triple in order to be safe and will be able to live with the risk of flood\dilution for this wonderful convenience. I figure that the odds of everything failing within a certain time period, such as a vacation are almost no existent. I was hoping that someone with a system like this could provide some more info on how they set it up. Links to supplies, and pics would be of most help. Thanks in advance!

[Meisen]

one issue that jumps to mind is that the initial product from most RO systems is often very low quality. The impact of always stopping/starting your RO system all the time may have a negative cumulative effect on your tank. While the DI can clean some of this up, IME the first few minutes of RO (Which is pretty much all you are going to be filling your tank with) are significantly higher in TDS.

No to mention the other risk you yourself point out.

A small resevoir system with dual shut offs on both the RO and the topoff system is probably the safest. Even with complete failure on either end, all you get is the 5-10-20 gallon bucket going in.

[KEstep]

Use a Kent Marine float valve or something similar. To be safe buy a solenoid valve and hook it up to an electronic float switch. Mount that float switch higher than the kent float so that if the kent float fails to stop the water flow ever then the electronic switch will shut off the solenoid and stop the ro from over flowing and diluting your aquarium.

[kff]

I use a bucket for auto-topoff and it lasts for a couple of weeks when I am on vacation. Not sure why anyone would want to connect their tank directly to the water supply. Things do fail, in ways that you can't always predict.

[baja_hammer2003]

Also check out oceanus systems they hook direct to a ro/di and have a 1-6 hour timer for top off and many redundacy features built like a tank www.oceanussystems.com

[rob020880]

Where can I get good qualtiy solenoids?

[chris4869]

You're pretty brave to hook up your auto top off system directly to the ro/di unit. I've seen float valve failed before, and it's not pretty.

[baja_hammer2003]

All tank crashs that i have ever read are from diy systems that people put to big of a load on the switch and that cause`s the contacts to fuse together. They are safe as long as they are protected from over current. bottom line if you don`t understand electricity don`t do it.

[Rouselb]

what if you put a solenoid valve on the RO unit, and set the timer for 1 hr a day. Using a float switch also. That way, every day for an hour, the float switch will be able to let RO water enter your sump. You could adjust the timer for whatever your evaporation rate is.

[baja_hammer2003]

If you still use a float switch to control a solenoid you would still be putting to large of a load on the float switch you need to use a ice cube relay that way the float switch is only pulling in the relay and not the large load of a solenoid.

[DarG]

Two floats. One is a passive that accepts the ro/di tubing. The other is a float switch that controls a solenoid. Small solenoid valve that runs on 12 VDC. http://www.fishbowl-innovations.com/products

The output from the DI flows through the passive float valve. The float valve and solenoid combination trigger the flow of the RO/DI. It is set up so that it is the float that controls the level. The passive float provides redundancy and only comes into play if the solenoid stays open due to failure of the solenoid itself or a problem with it's float switch. If this happens it will allow a little more water to flow than desired but that will be shut down by the passive float through which the top off water is actually flowing. It's the same way that I have my RO/DI storage container set up. If the electric valve fails and stays open for any reason, the passive float prevents overflow by stopping the flow.

The link also has a system sepcifically designed for auto top off. And can also be set up directly from the RO-DI ... I think.

I control top-off by controlled drip rate of Kalk and 2 part only. I'm not so sure I would use the type of auto-top off system we are talking about ... direct from the RO/DI unit. But, it would work, and failure, although possible, would be unlikely with two float valve system, one being completely non electrical.

[Rouselb]

hold on, thats not what i meant. I am talking about hooking the solenoid valve to a timer. That way it only opens for 1 hr or whatever you determine your evaporation rate to be. The float will let the ro water in only during that 1 hr period a day. This way, if the float was to get stuck, the solenoid valve would still only be open for 1 hr, and you wouldnt turn your saltwater into freshwater.

[DarG]

More stable by filling as needed and if the solenoid craps out and stays open the passive float will shut off supply. Also, RO/DI would be running more often and probably wouldnt need to flush any of the initial higher TDS water that you often have when the unit hasnt run for a little while. But timer would work as well.

[Rouselb]

We should just call it as it is: Safest: manually add ro water each day. Low Risk: use 3 floats. Mild Risk: use timer on solenoid valve and float. Insane: Wire ro directly to sump!!