Thread: Block build moving bed

Hi all. I'm planning my next build which I'm planning on being around 19k litres . It will be a block built and fibreglassed build with single bottom drain. I think I'm going to go with a filtreau 20 or 30 drum filter taking around 20k lph.

I'm now thinking about bio filtration and want to have a moving bed but my budget is now stretched! I find the bio chambers on the market to be expensive for what they are! I'd like a large chamber to accommodate potential future requirements...maybe 200 or 300 litres of k1. So I was considering throwing a few extra blocks up in the corner of my block filter bay and fibreglassing it when the pond is done. Then a 4 inch inlet and outlet with a diffuser at the bottom.

Has anyone done this? Can anyone see any issues with going for this approach?

This has definitely been done before and I've seen videos of it working well but can't think exactly where right now.

I think the main challenge is to create a tank shape, inlet and outlet flow and air stone positioning that will keep the media moving.

Get it wrong and you can end up with media all stuck against the outlet cage or pushed into a corner and not moving.

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(Has anyone done this? Can anyone see any issues with going for this approach?)
I have a 1.4 by 1.meter fluid bed that's 1.2 deep, contains 400 lts of k1 and boils away nicely!
Constructed the same as my pond concrete blocks lined with 25mm celetex and fibre glassed, 6 air stones in a loop supplied by a 60lts per hour air pump stuck to the base, to stop them floating.
4in supply from my drum with valve, to stop k1 going back, 2 pumps return behind a s/s mesh screen.

I got a filter grid and added mesh netting over it.for the bottom of the chamber.

Then glued steel mesh to the outflow chambers of my multibay bay 1

This then became a very scucessful K1 ,K3 bed where nothing gets out.

not got as much in as your requirements ( bout 60 litres - could add more but why get rid of good existin jap matt) but just letting you know a multibay can be converted without the expensive of super duper moving bed containers.



Jim

sorry it been a while been busy

heres my homemade K1 k3 micro k1 bedk1.jpg


filter grid with japp matting at the sides and two airstones in

wanted to keep some japp matt as seems daft to bin off fully matured media and all my eggs are not in one basket so to speak.
Stainless steel grid was off fleabay and got the bolts from screwfix.

hope that helps

Jim

MY moving bed is a wheely bin all kept very simple. 4 air stones one in each corner.. 4 inch pipe feed into the top. drain pipe with lots of small drilled holes (like a spray bar just more holes) in bottom 8" of pipe up to a y section then back out of side of tank. Water enters the top works its way down then back up drain pipe and out into pond. Y section is so i could add a cpl of inches of pipe to act as an overflow if little holes ever block up.

Originally Posted by Tinca

MY moving bed is a wheely bin all kept very simple. 4 air stones one in each corner.. 4 inch pipe feed into the top. drain pipe with lots of small drilled holes (like a spray bar just more holes) in bottom 8" of pipe up to a y section then back out of side of tank. Water enters the top works its way down then back up drain pipe and out into pond. Y section is so i could add a cpl of inches of pipe to act as an overflow if little holes ever block up.

I am thinking of using a wheel bin after my sieve and befor my K1 micro filter. Just wondering if you can post some pics of your bio filter and some stats ie amount of media, size of air pump etc. thanks