Hi

I have currently two water pumps, one near a lake then ten meters away close to our house a second one. During the dry season one pump was not strong enough to pump the water.

For the last years we did not have a tank, but i want to install one now.

Are these tanks normally filled automatically?

I probably would need to install a "switch" for the water tubing to change from filling the tank to suppling the water taps in the house? Other solutions? Pictures of solutions would be great.

I also have a tap for the garden and once this has been used there is air in the system, so once a faucet in the house is opend the air and water splashes out. Why is that? How to fix it?

Sid we use a 2000 liter tank . Very easy to install. The top of the tank will have an inlet. Attached to the holewill be a toilet ball & valve assembly(same as a toilet )the ball drops & fills when open & shuts off when full. Or plan B is an electronic float that floats up when full & sinks when lower in volume. You set the action on the electronic float to start when it fills & shut off when it is full or where you wan't it. The lower outlet goes to your second pump into your house & whatever hose bibs you have hooked up around your house.

Our settup has a PVC on -off on both incoming & outgoing lines in case you need to shut off lines. Ours is automatic with the mechanical toilet ball assembly. Last house we had to manually turn it on & off to fill That was 2 pumps one to bring up from the well & then after it was in the tank the other pump circulated the water into the house & around the house for watering.

Here is a picture on how we configured our tank. you can set it up without the shutoffs inline. It just makes it easier to work on later with a way to cut the incoming & outgoing lines.

Don't forget to install "one way flow valves", one between the tank and house and one between the water source and tank with the water flow toward the house. Also shut off valves so you can stop the water flow if you ever need to do repairs.

To our OP;-

Does your lake pump have an automatic pressure switch? The second pump? (this will determine how you control your tank level).

Does the lake pump have enough oomph to get water to your tank site and then up 2m to the tank inlet? If it does you can use it to fill the tank and the second pump to supply the house.

Do it something like this:-

Don't forget a 2,000 Litre tank weighs about two tons when full, put it on a decent concrete pad, ours has short piles too as we're on Bangkok clay.

EDIT If your garden tap is currently between the two pumps you could be sucking air if the second pump is running.