Tracking

Doghouse Riley · 24-09-2011, 11:13 AM

I'm raising this here, as I've not seen any comment on it recently, but it's something that should be considered.
We can see the water entering our filters and coming out, but not always what's happening in between.
Water will always take the line of least resistance. It's important that the water passes through every bit of the filter medium to get the optimum benefit from it.
If for whatever reason it misses a part of it out, this is known a "tracking."

Finflapper · 24-09-2011, 11:57 AM

Good point to raise. I have seen several filter chambers which have had Japanese matting slotted in. A good medium to use but loosely fitted is a classic cause for tracking. As alot of water passes around the sides of the matting it makes the filter inefficient. Some through flow filters have rubber seals on removable media panels and if not checked can let alot of water track underneath. Not good for retention time if your old school !

fosters koi · 24-09-2011, 09:11 PM

Hi guys, good thread doghouse, it makes me think how much water misses my filter medium. Hi flinflapper you said that jap matting is inefiecient ,i use jap matting in one of my filter chambers as i,ve got a large 3 bay old fashioned multi-chamber

(i want to replace it one day) and the matting seems to be falling apart slowly. And was just wandering what other,more efficient filter mediums could i replace the matting with. I use the jap matting after the brushes chamber so don,t know if that helps a bit. Any recomendations guys?

A.T.B
Paul

Doghouse Riley · 24-09-2011, 09:23 PM

I was aware (by talking to members of the North Koi Society) of this problem before I built my filters.
Even though they are only four forty gallon flowcore filled tanks, in pairs mounted on top of each other with 2" of foam above the flowcore in the top two, I designed a system to avoid any tracking.
The water enters through two full length spray bars in each of the top two tanks and is collected by two "reverse spreaders" in the bottom, the same process is in the bottom two tanks, so every bit of the medium is used.
I've drain valves in the tanks, so a couple of times a year I can drain out any fine sediment that collects at the bottom of the tanks and then give them a good flush with pool water.

pondy · 25-09-2011, 06:34 PM

surely if you cleaned it out once a month rather than a couple of times a year it would remove the waste from the pond quicker and therefore making the pond a nicer cleaner place for your koi!

think out about it, you cant clean mechanical filtration enough as the more you clean it the less waste in your pond/filters. draining off fines etc is a form off mechanical waste

Doghouse Riley · 25-09-2011, 07:23 PM

Quote:

Originally Posted by pondy

surely if you cleaned it out once a month rather than a couple of times a year it would remove the waste from the pond quicker and therefore making the pond a nicer cleaner place for your koi!

think out about it, you cant clean mechanical filtration enough as the more you clean it the less waste in your pond/filters. draining off fines etc is a form off mechanical waste

I don't think you've understood how my filter works, much of the coarse sediment tends to stay in the bottom drain and the connecting pipe, a bit more collects in the bottom of the 40 gallon pump sump as the filter pump is suspended a couple of feet above the bottom of the sump. This sump is purged and pumped to waste twice a week. What little gets up through the pump has to pass through the thick open cell foam on top of the filter medium. the more clogged this gets the better it works. What does get through is so fine, it's invisible. This is the clarity of the water going back into the pool.

But over several months some of this fine silt will build up below the "reverse spreader bars" in the bottom tanks. Because it takes eight minutes for the water to pass through my filters which hold near enough 140 gallons, there's not a lot of movement to disturb this sediment, during normal operation.
Whilst I'm getting this sort of clarity and always good test readings (when I can be bothered to do them), there's little point draining the filters more than twice a year.

Davej · 25-09-2011, 09:29 PM

Great thread DHR

As you say avoiding or mitigating tracking is something that can massively improve the performance of a filter, both in the mechanical and bio stages.

Just thinging laterally, for those with showers, is excessive flow with too little media of possibly no benefit other than to be able to brag that you have 10,000 gallons an hour going over your shower?

Dave

Gazfish · 25-09-2011, 09:34 PM

Hi Dave,

Yes i do think that you can have to much flow through a shower that doesn't have enough media and i also think some media prefers a slower flow and cleaner water.

Finflapper · 27-09-2011, 07:40 PM

Hi Paul, I think I said poorly fitted Japanese matting can be inefficient due to tracking. I think Japanese matting is superb and it might be a good idea to replace yours. All biological media comes down to one thing.. surface area ! Jap matting is very good at holding a good colony of bacteria. Alfagrog, which is a sort of lava stone is also good in chambers, usally the last one.

Doghouse Riley · 27-09-2011, 07:52 PM

Quote:

Originally Posted by Davej

Great thread DHR

As you say avoiding or mitigating tracking is something that can massively improve the performance of a filter, both in the mechanical and bio stages.

Just thinging laterally, for those with showers, is excessive flow with too little media of possibly no benefit other than to be able to brag that you have 10,000 gallons an hour going over your shower?

Dave

Yes, just as important as flow rate, is "dwell time," the amount of time it takes the water to pass through the filter. What rate this should be depends on a lot of factors, but it needs to be at a rate that gives the filter time to work. Too fast isn't good, neither is too slow.