Thanks for all your help and advice, we have now completed changing the ball valve, after talking to our local pond expert we bit the bullet and started to drain the pond, we already had a 13ft dia easy set pool, so we filled this with some of the pond water, the pond level was 23" when drain to the level to remove the valve, but the fish only had to put up with this for about 45min, just time to cut the old valve out and solvent weld the new one in, even after pumping the the water we saved back in the pond it then took 2.5 days to fill the pond back up through the purifier, we have two filter systems on the pond so we temporarily kept one going by pump feeding. All now back up and running for a week with spot on water results, the good thing by almost emptying the pond was we were able to see that we have no dead spots in the bottom, so the drains are working brilliantly, I must admit the fish did look alot larger in less water. As for adding an estro sieve, we plumped for another vortex instead, the cheaper option yes, now we go into the winter with sparkly clear water. One Scary moment late one night when the pond was filling back up, the water board pulled up outside to test the stop cock, perhaps they thought we had a leak............
Posted on Sep 4, 2006, 10:15 PM from IP address 81.79.126.178