Kh


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My test kit (API Pond Master Kit) does not have a test for kh....it just has ph, nitrite, ammonia and phosphates...should I be testing for kh also?
 
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And what do you do to counter balance if the rain water drops the kh.?
 
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I use baking soda. And I boost the KH before an expected rain to prevent any drop in the pH. It doesn't hurt anything to have a high KH, so there is no harm in running it up.
 
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Yeah the harm will be to my pocket book i'm sure for 12 to 18000 gallons that's a lot of baking soda that's needed. not that baking soda is needed but i can't see buffering pond water from rain when ever carp in the world deals with rain water in there ponds
 
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That depends on how much the KH needs to be raised.

Large bags of baking soda are $12 to $13 at Costco. I haven't bought one in several.months, so that may have changed a bit. But it's very inexpensive. I usually need one, rarely two bags a year for a 6000+ gallon pond.

It would be a lot more expensive to have to replace your fish that were lost in a pH crash. The proper level of KH will prevent that from happening. I think it's pretty cheap insurance.

Those wild carp you are talking about live in natural ponds that have a continuous flow of new water coming into them, from a spring or a stream. That new water is constantly replenishing the KH.

They don't live in artificial ponds that are recirculating the same water, constantly depleting the KH.
 
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It can, but I've never used it.

If it is actually rock, it doesn't dissolve very fast. Think weeks to months. In the powdered form it would of course dissolve much more quickly.

However, the more acid the water, the more quickly it will dissolve. Once the water becomes more acidic, the rate of dissolving would decrease.

Baking soda is easy for me and is what I have always used, so I'm familiar with it. And I'm older every day and don't welcome too much change!

But whatever works for you and your situation is good. Just keep an eye on the KH and if the limestone keeps that high enough for your pond, that's the main concern.
 
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I don't know unless your ph is way out of whack. I think you do more harm if adjusting is done too fast. Guess I'm lucky everything I bring a sample for testing everything is a ok
 
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Oh definitely, don’t go adding lime to your pond. I actually meant using limestone rocks for long term control. My apologies.
 
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Sorry, but I should have said that as the water becomes more alkaline, ( not acidic) the limestone will dissolve more slowly.
 
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You don't want to adjust the pH quickly. That will stress the fish. But if the KH is kept at a good level, the pH will not move. That's the whole point of KH. It keeps the pH stable. If you have very low or no KH, the pH can crash, killing the beneficial bacterial and your fish.

My pH is always 8.3 and has been for the last 8 years. It doesn't move because I keep a lot of KH in the system. KH is lowered by rain and by the acid produced as a by product of the nitrogen cycle. If it is allowed to be depleted, the pH will drop to acidic levels, very, very quickly.
 
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You don't want to adjust the pH quickly. That will stress the fish. But if the KH is kept at a good level, the pH will not move. That's the whole point of KH. It keeps the pH stable. If you have very low or no KH, the pH can crash, killing the beneficial bacterial and your fish.

My pH is always 8.3 and has been for the last 8 years. It doesn't move because I keep a lot of KH in the system. KH is lowered by rain and by the acid produced as a by product of the nitrogen cycle. If it is allowed to be depleted, the pH will drop to acidic levels, very, very quickly.
I'm confused... My PH is always around 7.5 but my KH is at 89.5...Won't adding baking soda bring my PH up?
 
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Yes, but it won't go above 8.3 or so, no matter how much baking soda you use. I keep the KH in my pond at 200 or more so my pH is at that level.

To me, your KH is a bit low. I like to see it around 100 at least. I have a bead type filter that I was told works best at a higher KH, around 200, so that is what I aim for.

A pH in the 8+ range is not too high. It's not a problem.
 
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Yes, but it won't go above 8.3 or so, no matter how much baking soda you use. I keep the KH in my pond at 200 or more so my pH is at that level.

To me, your KH is a bit low. I like to see it around 100 at least. I have a bead type filter that I was told works best at a higher KH, around 200, so that is what I aim for.

A pH in the 8+ range is not too high. It's not a problem.
Thank you for your quick response WaterGardener..I will add baking soda…my pond is only about 900 gallons…how much would you add at first? Do you think if I bring it up to 100 that would be okay? My plants are pale apparently due to low nitrate (my pond is only 5 months old ) so I hope a higher pH will not cause them to get worse…
 
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1 cup of baking soda per 1000 gallons will raise your kh 1 drop, so you should use just a bit less than 1 full cup. Mix it in a bucket with some pond water & pour it in an area of good water flow (I usually pour mine directly into the skimmers, or at the top of the waterfall) Wait 24 hours & test again, then repeat if necessary until you get the kh up to your desired level.
 
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The plants will be fine. Mine grow like weeds.

I just looked up how much baking soda is needed to raise the KH 1 drop. I get 3.37 ounces, just under half a cup.

It won't hurt to use a full cup of baking soda or more. Having KH higher than 100 is a good thing in my opinion, and it's difficult to have too high a reading. I will boost mine to 300 or so before heavy rain to make sure I would have enough to buffer that extra acid from the rain. Some people keep theirs as high as 400., So there is a very large range.

If you want to be cautious with raising the pH, add that one cup measurement over 2 or 3 days and not all at once.
 
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The plants will be fine. Mine grow like weeds.

I just looked up how much baking soda is needed to raise the KH 1 drop. I get 3.37 ounces, just under half a cup.

It won't hurt to use a full cup of baking soda or more. Having KH higher than 100 is a good thing in my opinion, and it's difficult to have too high a reading. I will boost mine to 300 or so before heavy rain to make sure I would have enough to buffer that extra acid from the rain. Some people keep theirs as high as 400., So there is a very large range.

If you want to be cautious with raising the pH, add that one cup measurement over 2 or 3 days and not all at once.
Thank you for taking the time to explain this to me. I will add the BS over a couple of days:)
 

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