Momotaros 150 ton pond

[koi4all]

whilst watching the koi-bito dvd saw them cleaning out the big pond which they said they do once a year why ? is it anything to do with the bakki showers.

rick j

[markgardner]

Rick

the pond is 1500tons!!!

The cleaning is nothing to do with the bakki showers, just to clean the system thoroughly.

Mark

[markgardner]

Rick

A pic of one of the 500 ton ponds being cleaned, this is a really thorough clean, jet wash and brooms scrubbing the concrete clean. In truth it really didn't seem dirty to start, it's not like loads of sludge was being removed.

[James P]

Mark, I was also curious as to why these ponds are cleared yearly? Do the showers sit idle during this cleaning process? How long does it take to clean and refill the big pond? Why do ypu think they do this cleaning annually? I notice they drained and cleaned out the old Jmat channels and filled them with bacteria house- will that be cleaned annually too? And why are they even using the old submerged channel system that surrounds the pond at all if they now have the showers? Thanks in advance. JR

[Dan Blatt]

Mark - What was this 500 ton pond used for primarily? Great photo by the way. Ah, now if that would only fit in my back yard.... I'd be a happy fellow.

[markgardner]

Jim

Yes the showers on this pond in question remained idle.

This pond was I understand going to be refilled within a day or 2, the refilling started after we left.

I don't know why they choose to clean the pond annually, i've never asked them. As i said above, it's not like they is loads of crap in them.

Submerged bacteria house, pass - don't know what they will do to clean this if anything.

Why are they using the submerged channel? Well i guess because they can only do so much at any one time like any of us. In April there was no sign of the new bakki only fish house, 7 months later it was fully built and operational. At the same time they were breeding millions of koi. A 500 ton pond would require a lot of showers installed, the pond, cast in concrete, may not be instantly changeable to showers.

Dan

When we arrived at Momotaro in April the koi was being emptied of potential male parent koi, see pic below...

[MikeM]

JR: I suspect the thorough cleaning reflects the mindset that the pond is interim housing between mud pond seasons??? Pressure washing away what algae there was, scrubbing out the media, etc. .... Everything Maeda does challenges our concepts of pond management. I think of annual New Pond Syndrome! But, I guess with 125,000+ gals being the "small pond", and a couple of thousand gals per fish being considered "full", there is a lot of margin for what we think of as error?

[James P]

Hi Mike, maybe? But I have seen a lot of filter bays in Japan over the last twelve years and they aren't exactly "clean"! I have seen systems taken out of service and painted, tweeked etc. But this seems like a rountine and commited cleaning program ?
Here's the thing I really don't understand and would like to- The bakki shower is a self cleaning unit that can manage all the organics thrown at it. The toxic effects of decaying organics, nitrate build up and heterotrophic domination are not a problem. The water benefits from this and the koi flourish in this bacteria active environment according to the inventor. But for some reason the same guy feels he must clean and scrub the system annually to --what? Keep it disinfected? Clean built up algae and attached waste? Remove nitrates? Honestly. It sounds like a contradiction? I'd really like to know the thought process. JR

[Mike Snaden]

As far as I was aware, the big pond gets cleaned out every three years or so. Daisuke told me in July that the pond is so big, with drains set so far apart, that cleaning has to be done, in order to scrub the bottom of the pond in order to clear it of dead debris.

Mike.

[MikeM]

Hey Michael. There is an inherent inconsistency in saying there are not enough bottom drains and the Showers handle all the solids, no? I'm in no position to knock results, and that's what counts! I just want everyone to get finished testing it out, and when all the human differences in maintenance regimes, stocking levels etc are worked out, I'll be ready to fit it on the new pond I have to build in a year or so. .... Wonder if the local tree frogs would like all those elevated wet areas? :P