bakki towers

[Roddy Conrad]

Siporax and/or Bioglass are terrific media for trickle tower constuctions, I have used both of them for many years. I suspect their properties in terms of surface area per unit volume and far infrared radiation at a decent match to the Bakki shower media. Siporax and Bio-glass are expensive just as the bakki shower media is expensive.

I regenerate the Siporax and Bioglass media in my trickle tower filters once per year by dipping it into pails of straight Muriatic acid from the building supply house. That removes everything but the ceramic media in less than 5 minutes, making the media "good as new". That regeneration process is "not for everyone", straight Muriatic acid is very corrosive, meaning mishandle it and you did not have a good day.

It will be interesting to see how long the ceramic media sold for bakki showers will work without surface area regeneration.

[Maurice]

I used siporax years back when it first came out in marine systems.
Sorry it's like talking apples and pears.
Pore size has no comparision.
Maurice.

[James P]

Hi Roddy, I'm sure that treatment would work but now that you have destroyed your biofilter and you have to start all over again- is that a good thing for the stability of a pond environment? This is why I have this annoying habit of reminding everyone that there are long term filter designs and short term filter designs. JR

[Roddy Conrad]

The advantage of Siporax or Bio-Glass or lava rock is a lot of surface area per unit volume compared to the "non-fouling" choices of bioballs and similiar biofiltration media.

The disadvantage for the high surface area medias such as Siporax or Bio-Glass or lava rock or the bakki shower media as JR so competently points out is that any of these choices will eventually foul most of the surface area, requiring some kind of "fix" to the fouling issue. The fouling becomes sufficient to warrant maintenance perhaps once every year or two.

I don't have any real issue with the "Muriatic acid surface regeneration process" for my high surface area per unit volume media choices, because I do not regenerate more than 25% of the total filtration system of a pond at a time. Meaning I have several trickle towers in service for the koi ponds, and take only one of them off line at a time for maintenance tasks.

As time goes on in my hobby, I choose bioballs more often than the other choices, because, like JR, I get tired of routine repetitive maintenance tasks, even if these tasks are only once every year or two. Okay, it takes a lot more filtration volume for the bioballs for the same biofiltration result, but they don't foul, and are very light to handle for any maintenance task.

If you are still reading this thread, JR, I am still curious to know how many of what size koi you keep in your 7500 gallon pond with its ~40% water change per week you described earlier? Filtration issues are stocking density dependent to a high degree, and I was trying to compare results some way or another. It would appear you run a quite large water exchange compared to my practices (5 to 10% exchange per week currently). If I exchanged 40% of the water per week, and kept less than 30 large koi in my 3500 gallon indoor pond system, I suspect I would need a lot less biofiltration capacity than I am running to achieve the same water quality.

[James P]

Hi Roddy, My numbers right now are fixed at 14. I will let it rise to as high as 18 but then tend to thin back to a dozen or so. I do the twice a week water changes and the daily ( in seasonanyway) sump cleaning so I have no alkalinity issues or no real nitrate/hormone buildup. JR

[Roddy Conrad]

Okay, you have half as many fish in twice as much water, so the stocking density of koi is about one fourth what I am currently running in my indoor koi pond for the Winter. Of course in the Summer season, these fish are spread out to both the inside and outside koi ponds to drop my stocking density by a factor of two, then I am only double the koi stocking density you run. I also change more water in the Summer, more like 15 to 20% per week in the outdoor koi pond.

With comparatively 4 times the fish load, and 1/4 the water exchange rate, I am effectively running a system with 16 times the demand on the filtration system currently to keep ammonia, nitrites, nitrates, and pheromones in the ranges for good koi health than you run. Certainly I am not alone in this problem!

Now I understand why my trickle towers are so much bigger than the ones I see in your pictures. In theory you could run 16 times less filtration capacity to achieve the same water quality.

I appreciate the answer to the question, that explains a lot of what you write, and helps me understand your view on filtration and water quality much better.

Again, thanks for the explanation and data, it is helpful.

[James P]

It definitely is overkill Roddy but the trickle towers are really not what I would call small- each one is 18 inches X 10 feet and holds 16 cubic feet of media. So that's 64 cubic ft of media! The manufacturer rates that for 2400 pounds of fish! I half that rating but still have only about 120 lbs of koi! JR

[Roddy Conrad]

Okay, then, that means you have the equivalent of 64 times 7.5 = 480 USA gallons of trickle tower capacity on that pond. I am running ~200 gallons of trickle tower capacity on each of two koi ponds, so if I combine all my trickle towers together on the two koi ponds, they are still a little less in volume your 4 trickle towers.

So I apparently was not interpreting your pictures very well, that is why I kept asking questions, to understand!

Okay, that means we are both way overfilted for the fish load, but you are at least a factor of 4 more overfilted than my koi ponds. Actually even more, since you use more water exchange.

I assume your supply water has a reasonable alkalinity to hold a constant pH and alkalinity through water exchange only. With a water supply "free of any alkalinity" at pH of 6.5 to 7, that is not an option for my ponds.

Again, thanks for the good additional remarks. They help me understand your point of views about ponding better.

[Mike Snaden]

Hi Roddy,

There is no way that JR could manage as well as you if he had 1/16th the filtration, and still have the same water quality. The water throughput won't affect ammonia and nitrite anything like as much as you imply. I would imagine that the filters remove ten times more ammonia each week than the water change would remove. If JR decided not to change a drop of water in a given week, he wouldn't experience a significant rise in ammonia or nitrite levels. But, if he removed the filters, and kept feeding in the same manner... the levels would go sky high.

Mike.

[Roddy Conrad]

While the water exchange rate may not affect the ammonia and nitrites significantly as Mike Snaden suggests, the water exchange rate will definitely affect the nitrate and pheromone levels just as JR says. Even with all that trickle tower filtration.

The nitrate and pheromone levels ARE important to the well being of the koi, even though most folks in the hobby pay little or no attention to them.

The drop in pheromones and nitrates with significant water exchanges is why JR preaches water exchange so often when writing about this hobby.

That is also why JR spends as much as he does on the water for the exchange. Exchanging 40% of the water per week on a 7500 gallon system would be 156,000 gallons per year for the water exchange. That would cost about $900 for the water exchange at our local charge rate for Charleston, WV, city water. JR's point is that it is money well spent for the health and well being of the koi.