Ph level is alway close to 9.0 only goest to 8.4 when adding vinegar but only last a day

[Mark Stell]

I have a 5000 gallon pond with 10 koi some large some small and bottom gravel filter ph has been above 9 for a while. Also have auto feeder for first time. Trying to grow my koi this year. Have food measured right so none is going into skimmer so seems to be working fine. I get lots of yard debris in the pond spring and fall and have to use pond sludge produce or bacteria to break it down. Have UV working. Clear water some white bubbles which looks like organic material is building up. My Salt level is currently .30

I am looking for help with lowering ph. I am wondering if it is my food volume or debris that is keeping my ph so high.

 

[Mmathis]

Hello and welcome! Nice pond!

 

[Lisak1]

Ooooohhh! Pretty pond!

How old is your pond? You say "bottom gravel filter" - is that all one thing? Like you have under gravel filtration? O bottom gravel AND a filter? A bit of clarification on that would be helpful. Do you test your source water?

Are these pictures current? You seem to have a small amount of foam which could point to DOCs (dissolved organic compounds) which can affect your water chemistry. Not sure how it affects pH exactly though - I'm not a water tester myself.

One thing most people will tell you - stable pH is more important that how high or low it is. Our pH was over 9 in our pond when it was new. Over time the pH came down all on it's own. I have no idea why, as we didn't change a thing.

 

[mrsclem]

Hello and welcome Mark. Agree with Lisak about ph. 9 is fine for koi. Might I ask why you have salt in your pond? A level of .3 is very high. How long has it been that way?

 

[Mark Stell]

The pond was rebuilt two years ago. I Have had one for twenty years in same place. Just went deeper and land scraped. But since buying some really nice Japanese koi I have been more diligent about keeping them healthy. The pictures are current just took them. I also think the doc’s are still high. I added the airration piece recently to increase oxigen after a suggestion. Someone suggested because of the rock in the pond I am going to have high ph but last year after being high it lowered to 7.5 during the summer. I don’t have any plants in the pond.

Also the gravel filter replace an old standard filter. Now I just have to clean pond once a year. Drain pond in winter and it does a great job with water clarity. I was told there might be a drip system if my ph is alway high and it will lower it when needed. Just curious if anyone has heard of a liquid acid drip of some kind to help manage ph?

 

[Mark Stell]

Hello and welcome Mark. Agree with Lisak about ph. 9 is fine for koi. Might I ask why you have salt in your pond? A level of .3 is very high. How long has it been that way?

I am only doing if for a few weeks I had a few sick fish and lost one this spring

 

[ShawnInfirmity]

pH levels can vary depending on the time of day AND will vary depending on the season/weather. In colder weather your pH will likely be higher than in the warmer months when organic material is decomposing and fish are eating and producing more CO2 and other waste products. As @Lisak1 mentioned a stable pH is more important than a obtaining a specific number. I would definitely not add products to try to change it unless it was WAY out of range and even then you would want to change it slowly so that the fish are not affected by a sudden change in pH.

 

[Mark Stell]

pH levels can vary depending on the time of day AND will vary depending on the season/weather. In colder weather your pH will likely be higher than in the warmer months when organic material is decomposing and fish are eating and producing more CO2 and other waste products. As @Lisak1 mentioned a stable pH is more important than a obtaining a specific number. I would definitely not add products to try to change it unless it was WAY out of range and even then you would want to change it slowly so that the fish are not affected by a sudden change in pH.

It’s good to hear that ph level is ok for the fish I have. I have always thought that I need to be around 7 for ideal. I was not trying to drop the ph all at once but was really co confused when it would drop and go back up after a little time.

 

[cas]

Nice pond. Do you measure KH and GH? My water use to have high pH until I raised the GH over 100. Now my pH says around 8.3.

 

[Mmathis]

@Mark Stell It’s more important for your pond to have a stable pH — more so than trying to achieve a specific number. If this hasn’t already been mentioned, one additional thing to test your water for is KH (carbonate hardness). You have to buy this “test” separate as it isn’t included in the standard kits. I’m not well versed in chemistry, but know that basically you want a high KH level (over 100-ish). KH indicates the water’s ability to buffer the pH, and keeps it stable against wild swings and crashes. (This, however, is not to be confused with and is independent of the natural little changes that happen throughout the day. ) My pond tends to have a low KH, so I have added crushed oyster shells to the gravel in my bog. Some people add baking soda as a “buffer,” but the oyster shell are more time-released. I think that “pH” (keeping it at a specific number) is more an issue with tropical aquarium fish. Just remember that “stable” (no wild swings) is your friend!

 

[sissy]

Welcome and I have koi and ph is around 9 and always has been and never worried me as long as it is stable .You start messing with things is when everything starts going wrong .My pond is also around 5000 gallons .I use only crushed oyster shells and koi clay in my pond .No other chemicals .

 

[Gemma]

I agree with leaving the PH alone, mine has always been that high, but I learned that trying to adjust it can turn out to be way worse that leaving it be

Welcome to the forum!

 

[sissy]

The scary one is ammonia ,that is to really worry about .

 

[Mark Stell]

Thanks for the advice I will leave the ph alone. My ammonia is fine. I think I need practice with salt bath as fish health is my main concern.