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[Rayscasa]

I have a above pond 4.0 x 4.0 x .800 deep above ground it consists of a nexus filter and uva three air stones a pre filter water fall
Water is clear but for the last month has been a night mare
All the fish are laying at the bottom like asleep
It started when they stopped eating and then they started all laying at the bottom all huddled together
Then I noticed a lot of blanket weed I done a water test the nitrate s seemed a bit high so I emptied 25% of the water out and refilled the pond but still the same put some chemicals in to bring down the nitrates down pulled all the blanket weed out and I have had some foaming where the water comes back into the pond
They move about but some just lay their look like there dead .?
My nitrates are ok ph is ok but to night a quite big fish and smaller gold fish was dead
I've put a pinch of food in but none come to it
Most of the fish are some European koi fan tailed goldfish and I have a lot of mosquito fish they seem ok swimming about .
It's not that cold to hibernate ?
Any ideas

 

[Becky]

Welcome to the forum @Rayscasa

A little more information would be useful here. Check out this list:

https://www.gardenpondforum.com/thr...-water-quality-algae-fish-problems-etc.12393/

 

[Meyer Jordan]

What is the actual water temperature? You mentioned Nitrate and pH, what about Ammonia? Nitrite? Did you test these parameters? What were the numerical results?

 

[Smaug]

Just saying the numbers are ok isn't clear enough. What is yiur actual ammonia,nitrite and nitrate numbers along with water temp.

 

[MitchM]

..
Then I noticed a lot of blanket weed I done a water test the nitrate s seemed a bit high so I emptied 25% of the water out and refilled the pond but still the same put some chemicals in to bring down the nitrates down pulled all the blanket weed out and I have had some foaming where the water comes back into the pond
...
Any ideas

What chemicals did you add?

.

 

[Rayscasa]

hi just lost three more fish a large fan tailed london feel a bit sick really the
air temp 50f 10 c
pool temperaure is 53f 13c
i have just done a strip test from OASE
nitrat 25
nitrit 0
gh 21d
kh 7
ph wert 7.4
ch 0

 

[Rayscasa]

this is the results