Cheap auto top up unit recommendation

[SteveMM62Reef]

Prism ATO, from BRS, and a Five Gallon Hedpack jug from Amazon. You could use a Six Gallon HedPack on your 135 +20 Gallon Sump, if it dumps all Six Gallons it won’t kill anything. Only had one Failure, the Prism part wouldn’t detect low Sump water, Prism Overnighted the replacement. I used a Rubber Grommet on the HedPack Lid for the Wire, and SuperGlued an “O” Ring on the outside of the Sump to position the Magnet.

 

[trini2debone]

I have a Tunze ATO as well, I don't regret getting mine in the slightest.

Okay thank you

 

[TehBrainz]

I currently use 2 float switches and my GHL profilux.

For years I used this though and it's still running strong. Just need to buy a small pump to go with it so I'd still say around 70-80

Hydor Smart Level Controller, Automatic Top Off, ATO https://a.co/d/03ul3W5C

 

[ScottJ]

I have been trying this one (Amazon link won't work) Pretty good price.

Fzone Auto Top Off for Saltwater Aquarium & Fresh Aquarium |Upgraded Controller| QST Alarm |0.7 inches| Dual Optical Sensor​

Only a couple month old, but so far, so good. I sealed up the joint of the sensor with silicone. I had another brand with the same type sensor leak. Couldn't just replace the sensor, had to buy the "new improved version" ATO. No thanks.

 

[mousehunter]

The 2lt bottle method does not take much explanation. If you have an adequately stiff bottle, and you submerge the lip of it underwater, it will only drain when the vacuum is broken - and then essentially only till the vacuum is reengaged. That said, it is annoying to put the lid of the bottle under water without it leaking first. The bigger the lip and heavier the bottle, the more annoying. You could use a 5 gallon carboy - but I have never flipped one of those into a dispenser and not made a bit of a mess.

I have done a few automatic water dispensers. Valves always leak. some valves leak faster than others. With my systems, that was more annoying than fatal. Abet I had animals go without water for a few days before I would notice it. On an auto top off, it would probably be less ideal. I have never used on with rodi water. Probably would be less destructive on the valves than the liquid rock that I was using.

 

[jermzisurmom]

Auto top off . Com

 

[VintageReefer]

Check amazon I got this one for $50 in March. So 4 months and it has done it's job for me.
WONICE Auto Top Off System- Smart ATO Lite Water Filler Refiller Advanced Water Level Controller w/Pump for Reef and Freshwater Saltwater Tanks Aquarium https://a.co/d/0ftvVTw5
I just got a bpa free cereal container. It's clear and fits next to my sump so it looks nice and I have to fill it daily but I like the involvement.

I use this same one. Works great

I use a 2.5 gallon container but you can use anything with a openin large enough for the pump to fit in