koi resting bottom still eating

[nellis1989]

I have a pond ive tried calculating gallons but every calculator gives me a different answer. it ranges from 1700gal to 2200gal. my pond is kidney shaped with three different depth. 9.5 ft long 6 ft wide...shallow end 2ft, middle 3.5ft and deep end is 6ft. ammonia nitrates and nitrites all read 0. pond ph has been swinging during the day from 7.5 to 9. I know a swing of this much is no good. my plants are browning and my koi are laying on bottom most dont stay long but my small 4" is "resting" a lot. all still swarm to feed. kh and gh are at 5 drops each. pond is going on its third month running. I had a 3000gph hooked up to a 1000gal flter and a 1000gal filter waterfall. I have recently upgraded to a 1000gph pump hooked to the 1000gph filter and added a 3000gph filter hooked to the 3000gph pump and 1000gph waterfall. The established filter is still in the pond. I have seen some flashing and done a pp treatment. I scraped and scoped for the first time since college and did not see any moving bacteria. But did see a lot of round looking things. not sure if this could be costia? Whent he koi first arrived in a quarantine tank due to 1 jumping out and i didnt catch it in time. the other i thought i caught in time but ended up dieing a few days later. I then lost one to a ulcer, i tried medicating with hydrogen peroxide and putting biobandage but i think it was just to late by time i got the ulcer as it was hidden on the bottom of the fish. Since putting the fish in my newly established pond i have noticed periodic flashing. Now they dont seem to be flashing as much but are laying on the bottom. I am not sure if it is due to the daily ph swings and if so how to stabilize the ph. I read it could be the stone around the pond leeching or the algae sucking up co2? I am a novice this is my first pond. I learn quickly but am at a loss. I do not want to lose my 4" koi who seems to be affected the most but a few seems to "rest" on the bottom. At this point I am at a loss. going to change the water tomorrow and see if that helps since i just did the pp treatment. also the regimen i found online was to do 2ppm pp wait until its brown do 2ppm again and wait till its brown then add a little hydrogen peroxide and turn on filters. wondering on advice for this as well....if the problem is costia will pp kill it? pond image uploaded

 

[Lisak1]

Welcome @nellis1989 ! I'm sorry that it is trouble that has brought you here but hopefully you can get some helpful answers.

I am not a water testing expert nor a fish health expert but there are others here who will pop in with some advice I am sure!

 

[Gemma]

Welcome to the forum!
Rather than a diagnosis on your fish I would be more concerned with the changes in PH cause if everything else is fine, that could be what's making your fish prone to sickness.

 

[nellis1989]

i am concerned on the ph spikes i am not sure what is causing it. I have some algae but not a ton and pond gets full shade in the morning and afternoon but in the hottest part of the day it has full sun. I am unsure of how to stabilize the ph. If it is the algae or if it is the bricks leeching into the water. I thought maybe it was rain but as the ph drops every morning and night, I was leaning toward the algae and not sure how to stabilize as i already did a pp treatment, which should cut down the algae. any advice?

 

[Lisak1]

Algae is not a cause for concern in a pond. You should look at it as a symptom, not a problem. It's telling you there's excess nutrients in your pond, which is very common in a new pond. It's also helping to control the very problem it's defining. So don't concern yourself with the algae.

What kind of brick do you have around the pond that is concerning you? I would also stop treating or changing anything until you isolate the issue with the fish. The treatments alone can be stressful, including water changes. It can also be very dangerous to treat a pond without knowing more accurately how many gallons of water you are treating. A 500 gallon swing is pretty big - that's a 25% difference from 1700 to 2200 gallons. From your description I would say at the MOST you have 1700 gallons (that's calculating an average depth of 4 feet, which might be high.)

It sounds like these fish may have come to you with problems - did you buy them locally? How many fish do you currently have in the pond? Did you add them as soon as the pond was filled? What kind of plants and how many are in the pond?

 

[j.w]

@nellis1989

 

[nellis1989]

There are 9 small koi in the pond from 4"-7" I treat at the 1700gal mark because it was the most common calculator response. there are no plants shelves in the pond just the three large shelves each about 3ft long. and the sides go straight down they dont come in at all.....i do have a lot of plants because i wanted to get different types and the hornwort took off like crazy. I have water hyacinths, hornwort, water lettuce and red ludwigia. I waited to add the fish until the pond was about two weeks old and I got an accurate reading of ph. I added beneficial bacteria as well about 2 days before adding the fish. Also each filter has a uv light on them. I bought all koi from the same place nextdaykoi.com they get all of their koi from blue ridge i believe and have a closed system.

 

[nellis1989]

I am not sure what type of brick is around the pond as it was given to me from my father who got it from my grandparents house before it was taken. I am guessing it is patio brick, I have read it could leach lime into the water and was looking into getting a sealant for the bricks.

 

[nellis1989]

I had no probably with ph readings until about 2 weeks ago, in which time i noticed a small spike in nitrate .25 and then it was gone. after that it seemed my ph could not stablize i have worked the water up from a kh and gh of 0 to now 5 drops. I just am not sure why ph is spiking during the day besides maybe to much photosynthesis going on.

 

[GBBUDD]

The first place that I would start is in looking at your pond is to raise the liner up a layer . it appears your liner is between layers of the block but the layer that's has the liner on it seems to be at grade this will allow water run off to enter your pond . i'd raise the liner up a level on your blocks if not two this will add more gallon and the more water the less your parameters change so fast. THEN YOU AT LEAST KNOW THAT ANY FURTHER CHANGES ARE FROM THE POND AND NOT ANY OUTSIDE INFLUENCES

 

[nellis1989]

the pond itself is raised above my entire yard. the liner is at the highest point of that hill and the block is on top of the liner. You are suggesting i put a layer or two of brick under the liner and then more brick over the liner? I am also going to be order crushed stone for around the pond, just trying to figure this our first.

 

[MitchM]

If your KH was zero you could have gone through a PH crash which would have reduced your nitrifying bacteria population.
You need to stabilize your water for the health of your fish. Stop all additives until we can establish the quality of your pond water and the source water. Let the algae grow for now.
Please test your present pond water and the water you use for water changes and post the results separately.

 

[Lisak1]

am not sure what type of brick is around the pond

In looking at your picture, I wouldn't worry about the blocks - it doesn't appear the water comes in contact with them at all.

I think the photo is also a bit misleading, as it appears the liner is laying on the ground. That may be why @GBBUDD is suggesting raise the edges. But I'm guessing you lapped the liner over the top edge and then folded the excess down to the ground, correct? I don't see any concern for runoff if that's correct.

@MitchM is well versed in water chemistry - you will get good information and advice from him.

I asked about the fish source as some of your initial information was a little confusing re: quarantine and fish jumping out and several dying right after you got them and another having an ulcer... how many fish did you lose initially? And be aware that at 9 fish you are probably at the max for this size pond. I know you said "small koi" but honestly there's really no such thing. That's like calling a baby a "small human" - we all know they're gonna grow!

One last question - are you sure the deepest part of this pond is 6 feet? That would be quite a slope from 2 feet to 6 feet deep in a less than 10 foot run. My math isn't great but that's like a 22 or 23 degree angle.

 

[nellis1989]

@MitchM My source water is very soft kh 0 gh 0 ph 7

 

[nellis1989]

@MitchM current water parameters this morning were kh and gh 5 drops ammonia nitrates nitrites all 0 and ph 7.5