Help me plumb a 125g for auto/semi auto water changes

[Greg5OH]

This is actually for my 125g discus tank, but I figure nobody has as advanced tank plumbing as reefers do. Doing 50% WC every 2 days with a hose and tap gets tiring..I want to make it so I have to turn a few knobs or have it automatic.
I fill my tank straight from the tap (well water). just adjust my tap to 84F out and I have a septic system. No need for aging barrels or ATO etc.



Tank is 6' long and it shares the back wall with my bathroom. it is not drilled.
I have a hot and cold water pipe right behind it and the wastewater drain from toilet and upstairs kitchen on the other side. The PVC wastewater drain already has a cleanout tap on it so would be easy to get into. The freshwater hot and cold are copper pipes and would just need to be cut and tapped into.

Two things I am looking for
-automatic temperature regulation of the fill water
-automatic shut off of fresh water to prevent over filling

I dont think i need to drill the tank for this since Im not running a sump, just one drain pipe over the side , terminating at 50% height, with a pump to initiate a siphon, some type of backflow valve on the drain to prevent sewage from ever entering (even run 2?) and some kind of temp regulating valve with an ATO style water shut off sensor?

walk me through this. I want it fool proof and redundant safety systems.

Thanks in advance!

 

[csb123]

Bump...I want to know too.

 

[ScottieB]

I think what your describing is manageable, but I don’t see how without a holding tank of water that’s heated. Then it could be plumbed with one pump, a float valve and heater on the holding tank and some ball valves like a saltwater mixing station.

You could use a saddle valve on the hot/cold water supply and a solenoid hooked to an on/off auto top device to fill the holding tank.

 

[ScottieB]

I doodled a drawing, not sure it will help but in my head it makes sense.

 

[ScottieB]

I missed a ball valve on the drain coming from the tank. Sorry.

 

[JDnKY]

AutoAqua AWC. But you’ll need a holding tank and drain close by. Set your sensors where you want them and push the button.

 

[Greg5OH]

No holding tank necessary, right now to fill the tank i hook my hose to the sink, and open my tap to where i have the hot water knob marked and it fills at a water temp of 84F. Takes about 30-45 seconds for the hot water to start flowing out but it fills maybe 1.5-2g out of 75ish that im changing so its not a big deal. My water heater is my holding tank.

Do I just run a hose with an inline pump for the drain? I would need a check valve (to prevent effluent backflow in an emergency) as well as a P trap to stop any gasses, along with a manual drain valve . Do I need to drill the tank for an overflow, or a pipe set in at approx 50% height (so you could never fully drain the tank) running over the back of the aquarium, into the display.
Would the AWC controller turn this drain pump on/off?

Saddle valve is too small. i would solder in a normal copper T fitting to each hot and cold supply pipe. Just wondering what kind of valve to tie the taps into, so I can set and forget my temperature. Just turn the valve on and the temperature is preset to 84F. Then the main thing is, I want something that will automatically shut the the fill valve at a specific height to not overflow the tank. This is where I think you are saying I need a holding tank (as you would run a DC pump or similar, which the controller would turn off). However I have no need or want for a holding tank...rather just have some type of device that Will open and close the fill water on a float/optical sensor.

I guess to simply my question
1) can I do an automatic drain then fill without the use of a holding tank? Timer is not necessary, but manually activate it, and have it automatically turn off the filling at desired height.
2) how do I plumb the drain exactly. Check valves, P trap, pump, siphon/overflow?

 

[JDnKY]

Problem I see is the tap water. Doesn’t it need to be treated to at least remove the chlorine/chloramine before introducing it into the tank? I guess you could hook up an RO filter, I wouldn’t use DI water in a freshwater system. The RO/DI systems can be hooked up with a float valve in the tank and proper pressure sensitive shut off valve on the filter, I’m sure RO systems could be as well. The drain can simply be a small pump with hose to the drain, you just need to install a siphon break in the line above the water line but still in the tank.

 

[Greg5OH]

Siphon break...will look into that.
Im on a well, have been filling my discus tank like this for 4 years, no issue. No chlorine in the system.
rock solid 8.2 ph, technically not the best for discus but they are ok with it as long as i keep up with the frequent changes. I try to keep it simple with them.
Feed them, frequent water changes, 84-84.5F water temp, and everything is all well with them.
They just love the frequent water changes, have them all spawning and eating like pigs.

You are not addressing any of the issues of going direct to a sewer line. Is a 1 way valve and traditional P trap enough?
If I have this system on full auto, which is the eventual goal: say every day 7pm, take out 20 gallons, and fill with 20, I need some type of automatic valves too...

 

[JDnKY]

With the siphon break you shouldn’t need a 1 way valve. As for the drain, if you can’t tap into the bathroom sink above the p-trap, I would put in a p-trap to stop gas backflow. To truely automate it you will need some kind of controller. The drain just needs to be a small submersible pump in your tank with flexible tubing and a siphon break dumping into any safe drain.

 

[Greg5OH]

Im thinking I can set this up with a neptune system. Not a DOS.
Essentially use (12 volt?) solenoid valves, and the neptune would control them.
I assume I can set up some safeties in it,
for example:
Drain sequence:
See that water is "full"
open drain valve,
start drain pump (located in the tank)
turn off drain pump when low level sensor tripped
close drain solenoid valve
Fill tank:
see that full sensor shows level low
see the drain solenoid is closed
open fill solenoid valve (water temp preset at the outlet)
turn off fill solenoid when full sensor shows full.
I would have a manual ball valve on the fills just in case the solenoids fail, I can shut the water flow off in an emergency.
I would also like to run a redunant safety sensor on the fill.

 

[JDnKY]

I have an Apex and am sure you could control it with one. I haven’t set mine up for anything like this but with the proper research, and a breakout box?, it could be done with the right solenoid valves and water sensors.

The only issue I see in your logic is that if you first check for “water full” evaporation will usually cause it to fail. You could instead create a subroutine to make your full sensor act as an ATO.

If (AWC not in progress AND full sensor < full) then open fill valve until full sensor is on.

An Apex is a pretty expensive controller just for AWC. I haven’t but have you looked into a reefPi controller? It’s a DIY controller but I really don’t know much more about it than that. There are several posts here on r2r about them.