Need help, massive beni problem in the whole pond

[aquitori]

Having seen Tan's pond a couple of times. It has some shade as he mentioned for the koi to hide from the direct sunlight. Also Tan's pond isnt really that deep, at best 3' to 3.5'ft deep.

Here is a diagram of Tan's setup from what I remember.

[saratogatan]

thanks everyone, more info:

bridge : 4 years old, my wife had it repainted it with some marine paint.
color food : not used.
Depth of pond: 44" on the side, 50" at the middle.

water parameter :

kh : 5 dh
ph : 8.0 (8AM) 8.0 (11AM)
NO2: < 0.3
total ammonia : < 0.1 (did water change yesterday)


generic-wise, the koi are from :
Sakuma (showa)
ogawa (showa)
maruyama (kohaku)
momotaro (showa, kohaku)
nogami (sanke)
ogata (gosanke)
Ofuji (kohaku)
koda (sanke, affected very slightly)

I suspect the source of my pond water. The ph used to be 7.5 for the last 4 years throughout the year.

I just thrown in some Plater of Paris bricks, will see how that get consumed.

stan

[MJShaffer]

We have had beni loss that could be traced to a specific event, and then occurred over a period of about 2 weeks after. Twice in the past 5 or 6 years we have had an equipment failure where there was no air being delivered to the airstones in the quarantine during extremely hot weather. In both cases we had kohakus lose beni (all the beni) during a two week period after the event, although water parameters were back to stable after the low air/high temp event. I don't know if you've had any such event, but it is a thought. We were surprised at how that one stressful event could knock the hi clean off a kohaku over the next few weeks, but it happened similarly both times. MJ

[saratogatan]

I am pulling my hiar out trying to come out with events that can be stressful to the koi. Nothing so far. We don''t have algea boom so far this year. there is some blue-ish type of algae in the pond, I don't know if that is the one mentioned in one of the Mike mentioned.

stan

[simon]

Hi all,
just to add, that you are not alone, my friend has just expieranced the beni falling off his koi, but its only effected three sanke, from one breeder. two koi were maruten sankes and of a very high class, they now look like half eaten ring donuts, the beni started to recede from the centre and spreads out, and does give a very slight hikkui look almost, we went through thinking everything food, water conditions sunlight etc. but with it only effecting sanke and from one breeder we put in down to genetics of those fish. alas he wont be buying from him anymore.

[saratogatan]

ph @ 7PM : 8.25

Looks like I messed up the kh test. I will redo it tomorrow.

The tap water's ph is the same as the AM pond water's ph, 8.0. the water is likely to be the cause.

stan

[Steve Nguyen]

Stan,

Any update on this? Did the problem went away after you switched the pellets brand? just curious to know what's the root cause.

Steve

[saratogatan]

things stabalized, except 1 kohaku. What I did:
- reduced water change
- reduced feeding.
- changed food.

stan