My pond build is slowly progressing (due to bad weather, work commitments etc.) and this is where I've got up to.
I'm updating as I could do with some advice from the wealth of experience on here (creeping over now!!!)
The original plan was to feed 1 bottom drain and 1 skimmer into a large sieve with a pipe pump to pump the water over a shower then back into the pond via a 4" return pipe. However this is going to cost me the best part of £2000 - scrub that way over £2000 - and I'm thinking I can do as good a job with a different set up. And then I could always add a shower later as the stocking level increases and run it off the skimmer.
While planning a bit of an improvement to the pond at my parents house, I was thinking about actually running this pond on air with K1 as the filter media. I'm thinking about having a settlement and static K1 section at the far end, all the way across the filter area you can see in the second photo. This will then feed into a longer section that will run all the way along the brick wall to the right. The section along the pond wall and where the sump is will be the area to walk.
Each chamber will drain to the sump and the return will be a 4" pipe that will exit at the base of the final chamber, go hoizontally across to the pond wall where it will rise vertically. A tee at the top will allow the air to gas off and the water will return to the pond through the pond wall just below the water's surface.
I'm happy with the the return but I'm slightly worried about two areas of the design.
1 - I haven't got room for a vortex so the settlement chamber will have to be rectangular with a sloping base down to the waste outlet. The static K1 will sit to the right hand side of this so that the left hand side is open to remove large waste / unblock the drain. I am worried though that this will be a little small for the pond volume (about 5,000 gallons) and the hoped for flow rate (around 5,000gph - though this will depend on the effectiveness of the air uplift and may be a lot lower). I'm also not sure how big a fluidised K1 area / voume I'll need - any advice guys?
2 - The bottom drain feed into this chamber will be very simple - the bottom drain is going to enter vertically through the base and I'll use a standpipe to stop it when it needs cleaning - no slide valve to block! This pipe will be above the base so I shouldn't get grit in the seal either.
However the skimmer feed will have to go straight into this chamber too. I am thinking of simply positioning the skimmer in the settlement chamber so that the water flows in and through the fitting at the base straight into the chamber. I think this will work but I'm not sure how to regulate the flow or whether it will be possible to in some way. I was thinking of a ball valve but then I think the flow through the skimmer will be restricted already by the 1.5" outlet. I am thinking of leaving the design flexible enough to add a shower run from the skimmer at some point in the future but would like to run it through the K1 filter to start with.
What do you all think? Is my idea possible? I reckon it is but wondered if anyone has a better idea on how to do it or if the area I've got for the filter area (3.2m by about 1.5m) will be large enough for the filter? I loom forward to your input!