DIY ATO I made for less then $20

[Tsancho82]

This is a Vacuum seal ATO canister I made for around $20. It works purely on it's own vacuum seal. The top left spout is the air line that gets glued to the tank at desired level. As you can see from the 2 pictures below. Don't mind the horrible glue job.
The lower left spout is the water release line, I added a small ball valve to this line so I can shut it off when refilling this canister or when I am doing water changes and maintenance.
The large spout on the upper right is the filler. There is a large ball valve that is necessary to secure that the canister stays air tight, along with sealing each spout and lid with tons of silicone.

SO here is how it works, the upper air line allows water to flow through the lower spout as long as it is not being plugged by the water. It's not an immediate stop but its less then a minute for the vacuum to create enough pressure to keep the water from being released. Depending on you sump size I would recommend you glue the hose just below where you want the water lever kept (maybe an 8th of an inch) because it will be over the line more then under it.

The most important thing to making this work besides making it air tight is to place the canister higher then you sump. If there is a bow in the air line the vacuum that the air line creates will pull water back into the line and not release the vacuum to allow water into the sump when low.

It's not a complete fix but it turns having to fill everyday to every week. Enjoy, hope this comes in handy for some of you, if there's anything I left out let me know.

 

[ngrubich]

Have you had any issues with water siphoning from the display tank back into the canister before it is able to establish a vacuum? If so, how much are you siphoning? Or is the breather tube also in the sump? It makes more sense for me for it to be down in the sump, but I couldn't tell for sure.

It's a pretty cool idea, and for <$20 at that!

 

[Tsancho82]

Both lines are in the sump. The way my return pump is set up in the sump, the water would have to deplete completely in the sump for my display to take effect. Plus I would have had to hang the canister from the ceiling in order for it to be above the tank.

I got water siphoning back into the canister when I had it on the floor and the hose was bowing because it was lower then the sump. But since I placed in on my salt bucket and got the line to angle up the whole way to the canister from the sump, it doesn't pull enough to go up the line. I'm gonna go to Goodwell one of these days and get a cheap night stand or something so I don't have to fight with it to get to my salt.

 

[mr.maroonsalty]

Kewl old school design that I first heard of back on DIBS.

 

[amber3k]

So glad you posted this! Two questions. What are the white connection where your airtubes attach to the container and why a filter? I attempted to make one but only used silicone to attach tubes. The silicone didn't stick so I was planning on sanding the plastic and tubing a little. Thoughts?

 

[Tsancho82]

So glad you posted this! Two questions. What are the white connection where your airtubes attach to the container and why a filter? I attempted to make one but only used silicone to attach tubes. The silicone didn't stick so I was planning on sanding the plastic and tubing a little. Thoughts?

The 2 white connectors on the left are 3/8 in. male to thread adapters, about $2.50 each at Home Depot. I drilled out the canister and they screwed right in, I applied a thick layer of silicone to those to keep the seal in and prevent leaking.

Not filter, filler. That is where you refill the canister, a large ball valve is needed so it can be closed nice and tight to keep the vacuum pressure in.

I would just cut the line were the glue was instead of sanding it if you can afford the loss of line, just in case you don't get it all, it could create a gap and allow pressure to escape. But it sounds like you are on the right track.

 

[amber3k]

Filter, filler. Oops!:hmm5: thanks for the reply.