matthelliwell wrote:

On 7 July, 13:00, Jim Hurley wrote:
Others will have advice on the hardness.

Let me congratulate you on having your pump off the bottom!

I think if I did that in my pond, I'd have all the dirt collecting at
the bottom and not being sucked up by the pump. What I'd really like
is a pond pump with a float switch fitted.

Somebody who knows will correct me if I'm wrong- but I thought that
was the point. Leave the dirt/sand/muck, and clean it out with a
proper tool [rake, shovel, vacuum] when it is needed.

My pump is in a skimmer- but my puddle/pond has a bowl shape in the
'deep' end & I am hoping that I will only need to clean it out every
few years. Meanwhile my pump is spared the ravages of abrasives in
its bearings & I'm not re-circulating muck.

Jim
[and BTW- to the OP-- Have you figured out what caused the water
loss?]