If the finishing of the pond is an urgent matter I would suggest you get one of the inflatable collar paddling pools and set that up as a temporary pond so that the urgency is relieved. B&Q sell those paddling pools in a range of sizes and I forgot about one down the garden all winter, it was full to literally overflowing, 10ft dia and about 2ft deep, and at one stage there was ice on the top though there were no fish in there.
What follows probably isnt the answer you were hoping for but I regret not having a bottom drain in my 1350 gal concrete shelled goldfish pond.
Since the pond isnt yet finished I would give some serious thought to either
1) setting a proper bottom drain BD and plumbing on the existing floor and then adding concrete to raise the pond floor to the appropriate level for the new BD, or
2) cut a trench through the existing floor, set a proper BD and plumbing in there and then repair the floor.
Personally I would favour option 1 as it is the easier to implement and over all it strengthens the floor, conversely option 2 would also weaken the floor. You could regain the lost depth by adding a course or two of blocks to the wall.
The BD could be fed into a "settlement tank/chamber" etc and from there you could either feed an external pump or place your titan in the tank/chamber etc etc. The flow from a BD is termed a gravity flow and it is better to gravity feed filters as the sediment isnt chewed up by passage through a pump. Your bioforce filter isnt really compatable with a gravity feed and would have to be pumped to.
The island leaves you with a presumable ring shaped pond and I think to get effective removal of sediment you would need to either have
a) at least two BD's placed diametrically opposed, or
b) mid to deep water returns which create gentle currents along the bottom which 'wash' sediment towards a single BD or multiple BDs
Have you left a "0" off the model number of the filter? Hozelock UK make an 18,000lph bioforce filter but not an 1800, if it is the 18,000 then I guess your are looking at pumping at least 7000lph and IMO your current 3 x 40mm plumbing, which I would guess are 49mm through out, is inadequate for the flowrate you are expecting. Your current plumbing will pass quite flowrate but the back pressure it is likely to create will significantly reduce the flowrate that the pump can deliver and also increase the pressure within the filter. I suggest you read up on mid and deep water returns or, as the Americans tend to call them, TPR's (tangential pond? returns. I suspect you will end up replumbing your returns and if through the wall, core drilling may be the easiest way to go. I too hate over the side plumbing and wiring and I have one in the pond pump with the cable feed through 19mm? overflow solvent weld pipe coming through the pond 'wall', 90deg bends need to be made via two slightly spaced out 45deg bends to that the cable is feedable.
I suspect you will be modifying the pond and if that is so I suggest that you be in a postion to tell the builder you want this, this and this, here, here and here etc
Koi and plants can be mixed though it is perhaps less common in the UK than in America and boards such as koiphen http://207.228.252.5/forums/ may be of assistance to you.
Photographs of your pond and plumbing would also be of help to people givung you advise. From memory the photo has to be on the web and you simply copy and paste the full web address of the photo where you want it to appear, starting http and ending, for example, with jpg,
Posted on Aug 26, 2006, 7:39 PM from IP address 81.76.74.180