I am constructing a pond 1 x 2 m about 2000 litres (400 gallons). Half of the pond is 2 m deep the other half 3 m deep. I bought a spider filter and have been looking at pumps. Does anyone know if a Fishmate 3000 would be good. I have 5 goldfish in an indoor tank that will go in the pond, not sure if I will get another few.