Auto Top off help

[Mike Latimer]

I have a slight problem, for my new tank setup I want to put in an auto water change system.
I thought I had it sussed as per pic
However once the pump in the tank stops pumping out the water change water there is nothing stopping water back siphoning through the pump and emptying out the tank.
One thought was to lift the pump to the height of the water change level so once the water change level is reached then is can not back siphon, however I will have an ugly looking pump half way up the aquarium.
I could put in the solenoid valve.
Some sort of check valve however it will have to open at a certain pressure.

Thoughts anyone???

 

[cromag27]

Two best options:

1. buy a peristaltic pump from spectrapure.
Or
2. the end of the hose needs to terminate ABOVE the water level in the water container.

Option 1 is the best route for long term reliability.

 

[Mike Latimer]

I have a slight problem, for my new tank setup I want to put in an auto water change system.
I thought I had it sussed as per pic
However once the pump in the tank stops pumping out the water change water there is nothing stopping water back siphoning through the pump and emptying out the tank.
One thought was to lift the pump to the height of the water change level so once the water change level is reached then is can not back siphon, however I will have an ugly looking pump half way up the aquarium.
I could put in the solenoid valve.
Some sort of check valve however it will have to open at a certain pressure.

Thoughts anyone???

Ahh good idea using a peristaltic pump although I need about the same flow rate as the EHEIM 600

 

[cromag27]

Then option 2.

 

[Mike Latimer]

Then option 2.

What about a check valve? I'm not able to implement option 2 due to where the tank is situated

 

[reefwiser]

You Say Auto Top off but you mean Auto Water Change?
I always use check valves in water lines.
Auto Water Change search.
There are systems like http://genesisreefsystems.com/products/automatic-water-change-systems/
I use one of my GHL doser 2 pump system.
https://www.aquariumcomputer.com/products/ghl-doser/ghl-doser2/
with level sensors to change a measured amount of water each day.

 

[cromag27]

I would never trust a check valve in this application.

What about a check valve? I'm not able to implement option 2 due to where the tank is situated

 

[MTWiley]

I would never trust a check valve in this application.

I personally use a peristaltic pump, check valve and terminate the connection to an air gap higher than the water level. When you're talking about something that can empty your tank or cause sewage back flow into your tank there's no such thing as too many precautions.