I`m building a new pond, it`s 4m long x 2m wide.
It will have 2 levels of being 0.3m deep & one level of 1.2m deep.
The 4m length will be divided up into the three levels.

So it will be 0.3m for about 1.3m,1.2m for about 1.3m,then about 0.3m for the remainder.

How many litres will it hold is my question - I need to buy a pump for it

thanks.