The set was purchased at a reasonable price to enable our goldfish pond in the garden over the winter by oxygenation. By operating with two balls side by side, it was possible, despite temperatures of -15 ° to indemnify a hole of about 50cm in the ice. The unit runs smoothly for several weeks. The delivery took place within a few days. Unfortunately, I have not seen the fish, probably they will stay in deeper warmer water layers, so I to their state nothing can be said.
