Saturday 22nd March 2008.
On a normal day, when I arrive at the farm in the morning the first job is to give the koi their first feed of the day. Then I go to the plant room and start the pumps to bring in the new water for topping up after cleaning the filters.
This morning the pumps would not prime very well and when they eventually did they would not run under pressure. This indicated that there was a suction problem with one or both pumps. So my job for the next few hours was laid out, strip the pumps!
When I built the plant room everything was made removable, all items in the system are built with either unions or ball valves each side so they can easily be removed. Also each pump has enough spare cable to lift them free so servicing them without disconnecting electric cables is possible (of course the mains are isolated before any work is carried out).
After removing all the pipe work the pumps were lifted out one at a time and stripped down. Both pumps had pieces of gravel stuck in the impellors.
I shall have to refit the suction box in the supply tank. There is a story why this suction box is not fitted anymore, perhaps I'll tell?
Outside of the plant room is a 400 gallon tank where all the new water is fed into the system. This tank was secondhand from the fibre glass company I used to subcontract to, although it does not need to be it is insulated with polyurethane foam. It is buried in the ground and the suction line is in 2" PVC pipe, on the end of the pipe is a large homemade strainer (the suction basket), this stops any large objects entering the system.
One day during a period of heavy rain the amount of water I was drawing into the plant room was greater than the feed supplying the tank. Slowly the level went down and guess what happened next.
The water outside of the tank due to the heavy rain caused the highly buoyant tank to pop out of the ground and I found it floating 18" higher with all the pipe work snapped off.
To get the water running after I had managed to get the tank back in the hole I ran a new pipe into the tank and have never reconnected it to the suction basket.
I must find time to do this soon!