Feel your pain, you should check your shower for a build up of muck, as I had the same problem with mine and it was the cause of my bacterial outbreak. And I had a pre filter but still crap gathered and caused issues. The foam can be due to them trying to mate at night. As I have noticed they are more active in that way later on in the evening and you will get tons of foam as a result. For the chat, I'd have a tub with mine 0.09% salt and add Acriflavin at a strong dose for about an hour per fish and do it daily till you get on top of it. Vircon in the main pond to combat it both ends. That's the approach I used with good success. Hopefully that will work the same for you and the cleaning you are doing is exactly what's needed before any treatment for maximum effects. Hope it works out🤞

Keep on going mate been there myself. Try a retro n maybe at a later date get rid of the shelves. My wife hates my pond now after all the money n stress its caused me but think iv got a good balance now 8 koi n a finely tuned set up enjoyed it again for the last few years. Came very close to giving up at times with dead koi, ruined koi fin mouth rot etc.

I also have a shelf and I doubt very much it's the reason for your issues. You mention that you haven't cleaned the shower in a year. I clean mine twice a year now and make sure to check it regularly to see if I have any build up. Showers should have as high an output pump as possible and for that reason I changed the spray pipe and put smaller holes in so it forces it out at a higher velocity and helps break down any crap. Hope some of this helps you get to the bottom of it and the dips will help. On the scraps, I would be looking at around the seven scraps, especially when you are having issues,cover all bases.

There is nothing like the sound of your koi slurping down food in the morning. Just subscribed! What is the challenge you’re having with adding an airline to you upflow?

I put a retro fit bottom drain in 2 yrs ago on an EA 20000 pump best thing I did, you wont regret it.

I started using virkon a couple of years ago. Research told me it helps get rid of all bacteria (good and bad) but the good bacteria reproduces faster than it’s destroyed. I’ve used it about four times this year so far due to an issue with one of my koi and all are looking quite healthy now. I also fitted a retro drain a couple of years ago so you won’t regret that either. Hard and frustrating work keeping koi but nothing to beat it when all is ok 👍

The fish are swimming around like they are perfectly healthy!

In the video there appears to be a lot of floating particles of vegetation debris, have you treated for blanket weed recently, because with the long summer days it grows profusely! I use the Evolution Aqua stuff which works well for me! I know you’ve done scrapes but are you sure you haven’t got Costia? Because the damage your fish have look like you could have! With Virkon I’ve found you need to hit with heavy doses if you have problems! I use 5-6 times the recommended dose on day 1 and then the regular dose on days 2,3,and 4. I then do a weekly filter clean and repeat the routine for probably 3-4 weeks! I use Virkon powder rather than tablets as you get twice as much for the same money! You get a bit more foam but it clears in a few hours! Never had it cause any problems with my filters! Good luck , I know it can be very stressful

i had big bacterial probs....id remove that chag unfortunatley .....yes use virkon ,,do some research as depending on water hardness you can and should do a mega strong dose ......same as acriflavin use that and again you can do a mega dose

You won’t regret the retro pal 👍

You have a stunning setup mate. Sure the retro drain will be a worthwhile upgrade. Stay positive, You will get on top of it all👍

Hi, interesting video, the joys of koi keeping! Liked and subscribed🤓

On the tempest issue with crap at the bottom, on mine when it’s cleaning I shut the drain valve when it half empty then take the top black cap off and shove an airline in from there and give it a real long boil, I’ve found this helps clear the bottom of the tempest. Good luck with the sick fish. I really like your set up and pond so please stick with it but I know how you feel as I’ve felt the same with my pond over the last couple of years .

Thanks for sharing. Fingers crossed mate hope all goes well. I am building my first pond atm and would like a shelf but cannot afford fiberglass so I am going bottom drain and box weld liner to avoid the folds. I wouldn't have a clue what to do with a sick fish..... hope the Vikron works..... Let us know how you get on mate. All the best

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