Best auto top off device?

[BBCoach4]

Hi:

Just wanted your opinion on what you all think is the best auto top-off device available at a reasonable price. I'm losing tons of water due to evaporation, and need to go to something else. Any info would be appreciated!!

Thanks!!

[gearhead]

tagging along.

[thereefgeek]

I built mine with float switches and relays, but depending on how accurate you'd like it to be, the Tsunami AT-1 is a simple & cheap solution. It's something like $50, but I took one appart and it's sickening how simple it is to build. Maybe a future DIY if anyone is interested. It is however limited +/- 1" of water level and in smaller tanks that could affect salinity quite a bit.

[WizardOne]

I built mine also and it will do both close level control or with a larger range if I use both floats. Works great

[BBCoach4]

Could anyone give me plans, or direct me to some?? That would be super helpful!!

Thanks!!

[CaptiveReefSystems]

the LLC that Spectrapure sells is what I use. No moving parts.

[dtny547]

I know a few people who use this:

http://www.californiareefs.com/home.htm

[thereefgeek]

For mine I got the switches at www.floatswitches.net and used a 12v adaptor to control a relay switched by the float so there was no line voltage in the sump. The relay kicks on a powerhead in a resevoir of RO/DI water and shuts off when the level is back up. Here's the electrical schematic and you can eliminate the little lights if you want. They were just to tell what mode (auto/off/manual) the controller was in.
http://reefcentral.com/gallery/data/500/43056FINISHED_CTRLR_40kb.jpg

[wombat2]

http://home.att.net/~s-pawlowskis/topoff.htm

A couple considerations--you need a tall stand to do this, and a sump. You can find a glass carboy and rubber stopper at Brew It Up! in Sacramento or any brewery supply type store. Don't even bother trying it with a plastic container or plastic lid because it won't work.

This is the cheapest easiet method IMO.

[wombat2]

http://home.att.net/~s-pawlowskis/images/TOPOFF.JPG

It is absolutely essential that everything is airtight.

HTH.

[plankton]

Matt,

There used to be a company that produced a product called 'Nurse' that does what you described. Yeah, you are correct in that it is based on a siphon and would need to be airtight. Also, the walls of the resouvour need to be rather strong to stand up to the pressure (or rather suction).

I also use the Spectrapure LLC-M
http://www.spectrapure.com/St_alc_p2.htm
and am very happy with it. Basically, I just use a 100GPD RO/DI unit to feed a 40 gallon commercial garbage can and the electric value which feeds the sump directly. Works great.

Scott

[wombat2]

Scott,
Does your RO/DI unit pump a little at a time or a lot at once? Wasn't able to figure it out from the link.

Thanks!

[Bamm Bamm]

I didn't want to dealw ith all the wiring and crap or anythign like that so I bought a Dual float switch autotopoff with a pump from www.autotopoff.com I think it was like $50 or something it works great.. I have a 20g acrylic truvu for my ro/di/Kalk reservoir and it tops off Ro/DI and kalk 24/7.. Best thing i ever did for my tank besides buying my ro/di

[plankton]

Matt,

The spectrapure couldn't be any easier to install. All you do is hookup the output from your RO/DI to the solenoid, so when the air switch senses 'low' the the valve opens and RO/DI water trickles into your sump; when 'high' it stops. I forgot how many cycles the solenoid is rated for but haven't heard of any going out yet. WRT the air switch I used silicone sealant to seal the suction cups to where I wanted the switch to be in my sump. The sump water line rises and falls about 3/4".

Scott

[Bamm Bamm]

remember when hooking up your ro/di directly to your topoff. If you have any issues your will have an unlimited amount of water going into your sump from your ro/di.. Many people do it with Sucess but it's the stories of the solenoids that stick and fill like 40gallons of ro/di into people sumps and cause the tanks to crash that keep me away from them...

[plankton]

Bamm Bamm,

The spectrapure setup comes with a regular float switch that the feed connects to (which I failed to mention); so, in the event the solenoid sticks in the 'on' position the float switch will prevent the sump from over filling. The solenoid is also normally in the off position so you are more likely to run out of water than to overflow your sump if power fails, etc. Power outage is yet another class of problem to be dealth with that I'm still working out...

Scott

[wombat2]

Originally posted by plankton
Matt,

The spectrapure couldn't be any easier to install. All you do is hookup the output from your RO/DI to the solenoid, so when the air switch senses 'low' the the valve opens and RO/DI water trickles into your sump; when 'high' it stops. I forgot how many cycles the solenoid is rated for but haven't heard of any going out yet. WRT the air switch I used silicone sealant to seal the suction cups to where I wanted the switch to be in my sump. The sump water line rises and falls about 3/4".

Scott

OK, so if I'm understanding correctly the RO/DI comes on in little spurts? Like it feeds the tank a few ounces at a time several times a day straight from the RO/DI unit? If so, this is taxing on the membrane and it results in a poor water quality from the unit, at least from what I hear. It's much more efficient (and you get a lower TDS) if the unit does a lot of water at once. I guess the first water out after the unit has been sitting is lower quality water. I don't understand the physics of this and haven't researched it a lot so...

[plankton]

Matt,

I'm not sure I get what you're saying. The water coming out of the RO/DI is slow since it has to go through not only the carbon prefilter, but RO membrane then usually another carbon finishing chamber then finally the DI cartridge. So, if you ever look at the flow coming out of a or your RO/DI unit it is 'trickling' out. I guess you mean you'd rather have the water trickle out and pressurize a ballast then feed the sump either as pressurized water or via a small powerhead to the sump. I don't how the pressurized output water will be any different but let me know if/when you find out anything. I do test with a conductivity meter and the water is normally zero (with relatively new RO membrane).

Scott

[wombat2]

Scott,
Some folks have their RO/DI unit fill up a topoff reservoir every few days all at once, and some folks have their RO/DI continuously on and plumbed to their tank. Just trying to figure out which one the LLC works on. It sounds like option 2, am I right?

OK, so this site helped me understand it a bit better:

http://www.reefonline.com.au/shop/default.php?cPath=37

It's called membrane creep. Basically when the unit is sitting and not producing water the water inside of the unit is higher in TDS than if it were continuously processing water. I think either way you feed the water to your tank your DI will probably drop it to 0 TDS, but it may be shortening the life of your DI filter.

Anyway after reading the SpectraPure site it looks like the LLC doesn't have this problem.

[CaptiveReefSystems]

A properly setup system would shutoff the water supply to the RO so it is not trying to product water all the time and creating a huge amount of waste water. Both Kent and Spectrapure offer systems with a pressure shutoff for the RO.

[plankton]

Matt,

I read the article you linked. Very good, detailed summary of how RO systems work. Nice.

I see now the part you were referring to and the solution to 'TDS creep' is to install a flush kit on your RO chamber to wash off all the minerals and crud and thus prolong the life of your membrane.

"The phenomena is commonly referred to as a TDS creep. A membrane flush kit will bypass the waste water flow restrictor (which provides the pressure for the RO membrane to work) and allow the full rate of feed water to flush across the membrane".

Scott