Depth of water.

[Russ Little Pond]

What depth of water needs to be above a Japanese matting bio cartridge ?

[ageinghippy]

Hi Russ,

To my mind, you wouldn`t have ANY water above the top of a cartridge, because if you did, water being what it is, it would take the line of least resistance, and by-pass the cartridge completely. Which you wouldn`t want.

Personally I`d have about a half inch of the cartridge sticking out above the water level so by-passing couldn`t possibly occur, even accidentally.


Chris (another one)

[Russ Little Pond]

Thanks for the reply chris.

[B.Scott]

That said, it depends on how water is traveling through your matting. Myself I have an over/under system with the water traveling vertically up through the matting which also has spacers. In this case I have about an inch of water on top of the matting

B.Scott

[Russ Little Pond]

I will be using a round vortex chamber with the water entering through a 4" pipe 12" from the bottom of the chamber coming up under the matting (10" thick) and leaving through a 4" pipe near the top.

My concern was getting enough clear space between chamber bottom and underside of matting (10" thick) without having the matting going higher than the exit pipe.

This is the chamber im looking at Kockney Koi MDPE Vortex Large

Thanks.

[Dick]

So what if the multibay chambers are 3ft deep? Are people now saying you raise the grid to allow for the supposedly correct 12" matting cartridge to just sit above the water line? Or are we to assume the return outlet is low enough to only allow the correct amount of water in the chambers for the matting to protrude above the water level with the grid left in the place they were designed to sit?

This philosophy makes no sense in having 3ft deep chambers if they aren't filled with water, surely?

[Dick]

OK, no real rush for the 'experts' to answer the above.

Oh and then there's air with matting. Air below matting or air above? Or no air at all as matting doesn't need it?

[B.Scott]

The main point is the matting must not be a solid block but instead have spaces in a checker board like pattern that allows a good exchange of water and nutrient to the bacteria living within the matting. I feel a vertical setup with the water flowing from below to above with air from beneath and an inch or so of depth on top of the matting to allow free flow to the next chamber to be the best way to go. I feel placing the cartridge in a vertical orientation keeps sediment deposits at lower levels and the raising air adds a slight scrubbing action to keep material from collecting on the matting but allows it to settle in the still water of the sump under the cartridge. The air flow also increases the ease of transport acting as an air lift. While the extra O2 is nice, I do not believe the amounts oxygen added from a couple of feet of bubble to be all that significant but none the less it does no harm.

B.Scott

[Dick]

The main point is the matting must not be a solid block but instead have spaces in a checker board like pattern that allows a good exchange of water and nutrient to the bacteria living within the matting. I feel a vertical setup with the water flowing from below to above with air from beneath and an inch or so of depth on top of the matting to allow free flow to the next chamber to be the best way to go. I feel placing the cartridge in a vertical orientation keeps sediment deposits at lower levels and the raising air adds a slight scrubbing action to keep material from collecting on the matting but allows it to settle in the still water of the sump under the cartridge. The air flow also increases the ease of transport acting as an air lift. While the extra O2 is nice, I do not believe the amounts oxygen added from a couple of feet of bubble to be all that significant but none the less it does no harm.

B.Scott

Thanks for that reply. So in your scenario a cartridge of say 12" tall leaving only 1" or so of water above the cartridge before it travels through the transfer ports of a 3ft deep multi-bay would mean lifting the grid a fair way up from its original siting and having the larger expanse of water below the grid.

It is certainly interesting how so many opinions differ on all aspects of Jap matting filtration but the cartridge design.

Does anybody really get very little crud on their matting or are these pictures we see online on occasions within a few minutes/hours of the water being on the matting before the muck appears?

[B.Scott]

Not quite sure how much room you have at the bottom of the chamber but I would think you would need at least 4"- 5" underneath the cartridge and at least 1"of water above it ( matting 1" below the level of the weir) Then however much room is in between is the how high you make the cartridge. For aeration I have a tube with holes on the bottom attached with cable ties to the eggcrate supporting the cartridge. Holes on the bottom all the pump to force out any water inside the tubes. If you put them on top water may collect in the bottom part of the tube.

[Dick]

Not quite sure how much room you have at the bottom of the chamber but I would think you would need at least 4"- 5" underneath the cartridge and at least 1"of water above it ( matting 1" below the level of the weir) Then however much room is in between is the how high you make the cartridge. For aeration I have a tube with holes on the bottom attached with cable ties to the eggcrate supporting the cartridge. Holes on the bottom all the pump to force out any water inside the tubes. If you put them on top water may collect in the bottom part of the tube.

The chambers are 3ft deep so 36" to play with. The grids are circa 12" from the bottom. The bottom of the 4" transfer ports where water would start to transfer through is circa 6" from the top. So 36" - 12" - 6" leaves 18" in between. Subtract 1" for the water above the matting and If we follow what apparently is correct and use 12" cartridges then we have 5" spare, meaning the grid would either need to be placed higher 5" to satisfy the supposed ideal, just make the cartridge 17" tall or make the cartridge 12" tall but have 6" of water above the cartridge.

[ageinghippy]

Hi Dick,
Welcome to this brilliant forum, hope you get lots from it.

I think you are getting a bit hung up with your interpretation of the cartridge size. In the 20 - 25 years since the 12inch cartridge was first recommended, an incredible amount of changes have happened. Originally the chambers we used were simply cold water tanks (as used in your loft), modified to be filters, so 12inches was perfect. Nowadays, a 12 inch would fit in one of the smaller commercially available fibreglass filter units, but most people have far better and of course bigger filter systems than those, and make/have made the cartridges to fit their particular size filter chambers.

Just had a flash thought * Have you had a read of Duncans excellent post `Japanese Cartridge Insight`, on the Koi Health page, it might tell you everything you want to know.

Hope this helps

Chris (another one)

[Dick]

Hi Dick,
Welcome to this brilliant forum, hope you get lots from it.

I think you are getting a bit hung up with your interpretation of the cartridge size. In the 20 - 25 years since the 12inch cartridge was first recommended, an incredible amount of changes have happened. Originally the chambers we used were simply cold water tanks (as used in your loft), modified to be filters, so 12inches was perfect. Nowadays, a 12 inch would fit in one of the smaller commercially available fibreglass filter units, but most people have far better and of course bigger filter systems than those, and make/have made the cartridges to fit their particular size filter chambers.

Just had a flash thought * Have you had a read of Duncans excellent post `Japanese Cartridge Insight`, on the Koi Health page, it might tell you everything you want to know.

Hope this helps

Chris (another one)

Chris, thanks. I'm not getting hung up in the slightest but merely wondering who professes to know what and why and for any valid reason why very few people actually agree with each other . It was precisely Duncan's post that made a point of a 10-12" cartridge and no necessary air. He also mentions he uses air above to avoid possible disruption of fines/muck that should be dropping, but just because he does and not necessarily because he feels air is that important in the filter. I agree with the air above theory to prevent pushing much up rather than seemingly allowing it to settle.

Methods of placing matting into filters vary. Speak to some and more water should be above the matting than just 1" inch, others say none but to have the matting exposed to air slightly. Then there is air on top, air on the bottom, no air!

I only feel these are what I'd call the basics yet I never read what I'd call definitive answers except to say everyone appears to be unanimous on the cartridge configuration now, even if the size appears to change annually.

My cartridges, by the way, are bigger and fit my chambers so I appear to be doing it my way.