Thread: Retro fit bottom drain.

I had one on a previous pond, I thought it was a useful addition, not as good as a standard bottom drain as you’re pumping rather than gravity feeding the filters. It will clear a fair bit of rubbish though, probably 4 ft pull effectively, not quite as effective as you get further out from that. My advise would be go for it

I had a standard retro BD and the only problem I had with it was blanket weed would block it if I didn't keep on top of the Aquasource Resolve treatments. Not planted, no shower or anoxic etc to remove the Nitrates and Phosphates just loads of static and moving bed K1 to add to the problem if you like. Ammonia and Nitrite were spot on.

I think the previous set up was better at dealing with the blanket weed. Pump with cage. The blanket weed surrounded the cage and then the pump would chop it up to a degree. Don't get that with the retro BD as the pump is too far away to effectively deal with any of the blanket weed.

My retro BD and pump pipework was fairly easy to remove from the pond to clean and remove the blanket weed. Not sure how much difference an aerated version would make if any?

The definitely do the job however, keep and eye on blockages of heavy leaf fall or blanket week debris.

Also they add a lot of equipment into the pond which can cause injuries from flashing etc.. and cause challenges when trying to net the koi.

Cheers

Gaz