WC's

[spdjnky]

I have been thinking of trying to use a pump like this.
Quiet One PRO 1200 (317 GPH) - Lifeguard

For water changes instead of the syphon. Was thinking of having a float sw setup that would turn the pump off and I would watch to so the setup would just basically do the work for me. Thing that gets me is i have not saw it do this way i can't be the first one to think of it so am I missing something.

[uvijaya]

I have been thinking of trying to use a pump like this.
Quiet One PRO 1200 (317 GPH) - Lifeguard

For water changes instead of the syphon. Was thinking of having a float sw setup that would turn the pump off and I would watch to so the setup would just basically do the work for me. Thing that gets me is i have not saw it do this way i can't be the first one to think of it so am I missing something.

Automating water changes needs to be well planned as it could turn into disaster. You could have a pump set up and manually turn it on and off when you do the water change. Its 100% safe

[spdjnky]

I just want the float sw's for accuracy I will be standing right there and it's only a short distance to the drain line. I have a PVC syphon setup that will stop auto at the 16 gal mark but it's slow.

[kmbyrnes]

Switches will lead to problems. You will get lazy and that's when they will fail.
If you are concerned about accuracy this idea may help.
Turn off your pump, let the tank drain to the natural water line and mark that on the side of the tank.
Manually remove and measure out water into 5 gallon buckets and mark the water level at each interval until you reach your desired WC amount.
I placed a piece of painters tape on the back corner of my tank and marked the intervals there.
Now I just pump out water til I reach my line, refill to the zero point, and restart the main pump.
I can do 25 gallons in less than 10 minutes.