Sickness

[Yigal]

My outdoors pond is 3 years old, with few Kois, gold fish and Gambusia.
Lately all the Hornwort (I think that's the name) died and the Kois start having stains on their back.
One gold fish lost most of it's gold color.
However, they look happy and normal.
Also the Gambusia seems to be happy.

Any idea what can it be?
Probably some kind of a sickness?

The pond has a combination of light and shade, and a good filter.

Thanks
Yigal

 

[ShawnInfirmity]

First thing I would do is test the water for pH, ammonia, nitrites, and nitrates and post the results. If you don't have a liquid/drop test kit we recommend the API Freshwater (or "Pond") Master Test Kit (https://www.amazon.com/API-FRESHWAT...pID=51FQhbpfB0L&preST=_SY300_QL70_&dpSrc=srch) Water quality issues are almost always the cause of fish illness or disease.

Also, the koi's back looks pink in the picture. Would you say that is an accurate description of the color? It could be inflammation due to an irritant that has entered the water somehow. Is it possible you had some runoff enter the pond with some fertilizer or pesticide from the surrounding landscape? Others will likely chime in soon and maybe they will have seen the markings before and might be able to pinpoint the cause, but I would definitely make sure my water parameters are within normal limits.

 

[bagsmom]

I can't speak to the rest of it, but I have goldfish go totally white after being fully orange. I heard some others say they sometimes turn back again!

 

[Lisak1]

Welcome @Yigal !

It's hard to say much from this one picture, but as @bagsmom said, fish can change colors, sometimes very dramatically. I have one goldfish that is constantly changing from white back to orange and then white again.

Can you tell us more about your pond - size, filtration, how many fish, how big, your location. More details would help a lot. And also if you test your water those numbers are important.

 

[Yigal]

Thank you for the replies.
The pond is 2 meter long, almost a meter wide, and 0/8 meter deep.
Fish count: 4 Kois (started small, now big), 6 medium gold fish, 8 Rosy Barb and about 40 Gambusia.
It is located in a sunny place, but partially hidden by trees.

The PH is good. I dont have access to measure other parameters - would you recommend me to do so?
I dont think there is a leak from the outside.

 

[Mmathis]

@Yigal Hello and welcome!

Yes, you should get a test kit for ammonia, nitrites, nitrates — at the very least — and please give us the results in the numbers that you get (instead of saying “it’s good”). The numbers can tell us a lot.

Also, you say you have good filtration, but can you tell us what your set-up is? How much water does your pump move, what kind of a filter and how big is it?

It sounds like your pond is a little on the small side, especially for koi, but sometimes you can get by if your filtration is really good. Unless My calculations are wrong (which is highly possible), that comes out to less than 500 US gallons. And you’re already seeing the koi grow. As they get bigger, they produce more waste.

Can you post some pictures of your pond for us — different shots, from different views if possible. We really like seeing other members’ ponds!

 

[Yigal]

I will measure again and come with numbers. Sorry. I agree.
Can you recommend sucha measurement kit? Is it Chemical based on electronic based that can measure automatically?

About filtration: I have a Lugona pump of 500L/h, and FiltoClear 6000 filter - from 3 months ago.

I attached a pic pf the pond - when the green was dominated. Before they started to die.

 

[Stephen Noble]

Hi Yigal, I agree with Shawn and Mmathis about the need for 'hard numbers' on your water quality. Taking a guess here...
Your vegetation's explosive growth was probably due to excessive nutrients. When the plants 'crashed' (died off), the biomass began decomposing spoiling water quality and consuming vast amounts of oxygen leading to a condition called hypoxia. Sometimes goldfish lose color due to lack of pigment stimulating sunlight. Poor breeding, changes in water quality and temperature and age are just a few other reasons. The streaking on your Koi could be ammonia poising or some sort of bacterial infection from the water quality. Your pond is experiencing the maturation process. Perhaps your fish have grown or even reproduced in the past three years. This increase in bioload, with all things remaining constant (frequency of partial water exchanges etc) could lead to overwhelming the filtration system. Again, I'm just guessing. Individual, liquid based test kits, not all-in-one test strips are your best bet for measuring water quality. Please let us know how it goes.

 

[j.w]

@Yigal

 

[Yigal]

I measured the PH on a daily basis, 2 times a day. It is stable on 7.

 

[Mmathis]

I measured the PH on a daily basis, 2 times a day. It is stable on 7.

Interesting. And it never varies? Not from day to day or from morning to evening readings?

BTW, how are your fish doing and were you ever able to get the other water test kits?

 

[Yigal]

It is stable - I use the color papers to measure, so it is not that accurate.
And no - I didnt get the kit yet.

But now I water the garden with pure water - no chemicals. and no change,