DIY Auto top off with safety back up!

DRC Archive General Saltwater Discussion
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DOH!! Sorry guys!

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Shawn,

The distance from the top of my sump to the desired water level is 5 3/4". The measurement for the width of the frame on my sump is 3/4" ( I think this is what you wanted for the green line).

Let me know if these are what you need.

Ellen

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Poifect! Thanks!

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Shawn, can you run a test for me/other users that want to use your ATO?

Setup the unit like you did at Armco and simulate evaporation, either through heating the water and running a fan over it or by setting up a drip to another bucket. I would like to see how the unit functions without a hysteresis (do the $100 units have one?). I am curious to see if near the ‘fill’ point the unit cycles on/off. Also I would think a solenoid would be a far better choice for this as running a pump for ~1 second wouldn’t make much sense when you could simply gravity feed in the ‘mix’ (RO/DI). If you could include a video that would be awesome. A hysteresis is something commonly used in temperature controller algorithms that basically waits until you go past a set point and over then slightly over shoots to provide a buffer from error in measurements. I worry that near the ‘fill’ point the pump will cycle on/off, ‘click, click click click click click click click’.

Gracious.

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I think your thinkiny WAY too much about this, but ill try to address some points.

By no means is this a precisions topoff unit and neither are any of the hobby ATO. The mechanism is very simple. The range of the solid state switch(the distance required to open and close swich), the diameter of tubing used for topoff, and the flow rate are going to determine the accuracy. I agree that a solenoid is better, and that is what i use. However, a low flow pump works absolutely fine and this is what 99% of hobbyists use. Its also why i demonstrated with a pump, i wanted to make it plug and play and appealable to the most people.

I have never heard of a hysteresis, but using your definition as context, i assure hobby grade ATO do not use one. No matter what, using an ATO is better than doing manual topoffs. If your looking for more precision, i would suggest you use a 1/4" solenoid with a ballvalve and drip your topoff.

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Can you run the test? Best way to answer a question is proving or disproving via a representative experiment, it looks like you have all of the materials already made up and would be as simple setting up a drip out tube and pressing record on the video camera.

Just giving my experience from writing MANY set point maintenance algorithms. Accuracy isn’t what my question/concern is about, it’s the constant on/off of the pump/addition device. In fact it is quite opposite and might be too MUCH precision. IF it is a problem I’m pretty sure it could be easily solved by some cheap electronic components added into the system. By no means am I trying to put your system down, just trying to head off possible failure/unwanted points prior to getting to far into it. Like I said just coming from experience creating set point maintenance controllers.

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Can you run the test? Best way to answer a question is proving or disproving via a representative experiment, it looks like you have all of the materials already made up and would be as simple setting up a drip out tube and pressing record on the video camera.

Ian, i have no idea what your talking about. Ive been doing your “experiment” for 4 years. The switch closes the circuit, the water fills, the circuit closes. Again, the frequency of your topoff which would determine

the constant on/off of the pump/addition device.
is going to be determined by the method you use to fill the water. If you use a 1/4" solenoid, expect it to be constantly opening and closing. Since most solenoids are rated at hundreds of thousands of cycles, it shouldnt be an issue. If you use a larger pump, and larger diameter tubing, it will cycle on/off less often but may cause stability issues smaller tanks. Regardless of method, the only
possible failure/unwanted points
would be a quicker EOL for said pump or solenoid and it wont topoff when it fails. The “failsafe” part of the build will prevent a disaster, because it opens the circuit.

In conclusion, if you prefer your topoff device wether it be pump or solenoid to cycle on/off less frequently, the solution is simple. Modify the length of the shaft of your SS switch.

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I thought you said you used the ‘$100’ model for your ATO? To me that means you don’t use your home build for an ATO or did I mis understand?

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if you made a video of this and put it on youtube, i bet it would get 50,000 hits easy…(not that ur looking for 'net fame)

I dare you to type DIY ATO on youtube, scary…wait till u find the video of the 15 year old, biting wires…its great

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My bad. The one ive been using on my DT is a DIY with a triac chip. The one for my solana i purchased.

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Any ATO can fail at some point, but with the extra float switch it gives you a measure of insurance. I have the JBJ right now on my 95 and it has a timer which shuts off the pump after 3 minutes. This works out fine for me as it only takes my pump about 1.5 minutes or less to fill the sump enough to trip the float and turn it off. I use the aqualifter pump because it has a slower flow which lets the pump run for more than a few seconds.

I paid top dollar for my tunze ato and after 6 months the electronic eye failed. I am looking forward to trying out Shawn’s DIY ATO as I think it should work just as well as the more expensive options.

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Shawn, can you video your current DIY ATO? I’m not down playing your ATO, I simply want to see how it functions.

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Shawn, I’d like to order one of these and I sent a PM to you (in fact I sent several) but I can’t tell if it went through.

John

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Sorry John, i havent gotten any PMs from you. Im hoping to have 3 or 4 for the meeting. Ento_reefer and Icy have spoken for two, but you now have dibs on the 3rd.

Edit: I actually just got a PM from you with the dimensions. Im remodeling my bathroom and fishroom, so there’s probably little chance ill have it ready before the meeting, but ill let you know if ido.

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HJack Pictures of the fish room remodel are required

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Maybe, as long as im not asked to make a youtube video to prove that my fishroom works Saint:)

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Shawn is hiding the fact that he simply doesn’t know how to take videos…

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lOl

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[quote=“Adictedtoswf, post:20, topic:634”]
I will take one as well Shawn. I don’t know what the distance should be but I planned on using the standard 55g for the sump if that help at all.

Thanks[/quote]

I though I was third if not second in line.

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Sorry Addicted, your right, i lost track. I will do my best to have 4 ready for the meeting.