It is far larger than I expected it to be..lol... Could have used more deep spots though but digging there is limited and I don't want to put too much pressure on the liner.
I guess, from the surface dimensions 10x5 meter and average at 1 meter deep, it is about 8000 gallon for the pond itself.
Add another 2000 for the settling-tanks and the 2 bog-areas.
Might be underestimating it, but think it's a fair guess.
Have put the second bottom-drain under water and straightened out the liner a bit. Now wait a couple of hours to see if that one holds. Also have to wait for the dome to be ready, don't want to mess up the silicone under the liner by pulling too much. The dome will nicely avoid that with its weight.
If all ok, then tomorrow we'll go to 50-70%. Later today more sand on the left side and back side to bring that up to full height.
It's murderous hot there, 20 minutes and soaking in sweat. Can't wait for rain-showers here...lol