So i thought i would top my plastic balls up in the tank but not looking forward to the tedious puncturing of holes in them. So thought I would check the supposed specialised balls for baffling my tank.
As you may see from the screen shot they recommend 1 small ball (same size as soft plastic play balls im using, i think) for every 7ltrs of water. So 500ltrs max = 71 // 72 plastic balls!! Doesnt say about size of the container or filling size of the container with them but a simple recommendation of 1 ball per 7ltrs of liquid.
Went on another sight and when i saw the price.......im now looking forward to the tedious puncturing of holes