POROXIDE AND OYSTER SHELLS

[sissy]

There was something posted last year that had how to lower and raise ph and baking soda was to raise it and not sure what they said lowered it .They were both posted at the same time .

 

[Waterbug]

OK, so is there anything that can lower the PH (I really don't want to use peat moss, as it makes the water brown ...) and then I could use the oyster shells to hold it there, if I remember correctly ...

Acid lowers pH after it consumes the pH buffer.

Oyster shells are mostly calcium carbonate which has a pH of 9. So in theory it would hold pH at 9. But there's other factors, like whether it's crushed or not, the amount compared to water volume and time. Oyster shells are very slow to raise pH. Here's a study done by a high school kid on The Potential of Crushed Oyster Shells as pH Buffer that shows in a 3.35 pH acid crushed oyster shells raised pH to 5.63 in 2 hours. The study's numbers for 7 pH water looks screwy, seems to have raised 7 to 9.5 instantly which can't be right. High school kids.

If you scale the amount of crushed oyster shells in the study to pond size...a 1000 gal pond would need 4,175 pounds of crushed oyster shell. That kind of matches what you see in aquarium keepers where they use a huge amount of crushed oyster shells compared to water volume.

Oyster shells are used in high end Koi ponds mainly as bio filter media. They may contribute some pH buffering but it is not relied on because it is so slow. If pH is driven down by rain or bio filtering the oyster shell is slow to react. Rain is a sudden problem because you get a pH swing. But large down pours aren't common. With bio filters there should be some middle pH reached. The level depends on how fast the bio filters are producing acid and how much oyster shell was available.

Baking soda is more commonly used instead of oyster shells for pH buffering because it's instant so pH is more stable. GH is used to hold pH down to 8.3 Baking soda has a max pH of 10 something and so without proper GH pH can drift into 9's with baking soda.

How oyster shell pH effects pH would be a pretty easy experiment to do.

So the bottom line is if you really need pH buffering, because of soft source water or high fish load/ high feeding, oyster shell is not a good choice. With hard source water, light fish load, oyster shell is fine. Oyster shell is also great bio filter media or if you just like the idea of oyster shell.

 

[fishrich]

bicarbonate of soda will buffer the ph to 8.4
What value will the shells try to buffer the pond to? some use plaster of paris in blocks as a ph buffer, i think im going to try it. They used to sell it in pet shops in blocks for ponds. I went into my local fish shops for a ph buffer as we have had lots of rain and my KH is low now, but they stocked nothing to buffer a pond.

 

[Waterbug]

Baking soda, bicarbonate of soda, NaHCO[sub]3[/sub] has a pH of 10.329. To get it to buffer a pond to 8.4 it has to be paired with a proper GH level. That will keep the baking soda from pushing pH up beyond 8.4 and into the 9's.

Many materials can be used to buffer a pond at many different pH levels. Plaster of Paris, oyster shells, concrete, egg shells, and many other materials will raise pH if pH is driven low enough to break down the material. So if you put a little Plaster of Paris in a pond and pH is driven down by rain or other sources it will eventually raise pH back up. Unfortunately not until after the fish are dead.

What experienced fish keepers look for is stable pH which is an entirely different matter. They want something that acid will react with instantly no matter the amount of acid. So they use materials that dissolve in water like baking soda.

 

[fishrich]

my GH is low I would say at around '6' and the KH is around 6, PH 7. What should I use to raise the GH and KH?

 

[fishrich]

I always thought bicarbonate of soda had a PH value of 8.4 and have never heard any other than that. Wikipedia could be wrong with 10.3?? What is right?

 

[Waterbug]

Oops, wrong scale. Maximum pH of baking soda in pure water is 9. Thanks for the catch.

You will often hear in pond forms and pond web sites that baking soda has a stable 8.4 or 8.3 pH. And for most ponds that is true because most ponds have GH in the 150-250 ppm range so it's rarely mentioned. Plus I think most people just repeat stuff without any actual understanding. There are more of those kinds of people posting stuff on the web then there will ever be of people who have some understanding of a subject. So the result is a lot of incomplete info.

GH of 150-250 ppm causes excess carbonate ions to precipitate out of the water, which stops pH from rising above 8.3. So baking soda is keeping pH from falling below 8.3 and GH is stopping the baking soda from raising pH above 8.3. Result is stable pH at 8.3. However, there are many things that affect pH so results can vary.

GH can be raised by adding say a pound of calcium chloride flake (from hardware store for deicing, 77% calcium chloride, or swimming pool supply) per 1000 gals. And say a pound of Epsom salt per 1000 gals to add magnesium. Water test to confirm results. GH is not consumed like KH so generally once you get to the desired level it stays there, excluding water changes.

 

[multifasited]

Oops, wrong scale. Maximum pH of baking soda in pure water is 9. Thanks for the catch.

You will often hear in pond forms and pond web sites that baking soda has a stable 8.4 or 8.3 pH. And for most ponds that is true because most ponds have GH in the 150-250 ppm range so it's rarely mentioned. Plus I think most people just repeat stuff without any actual understanding. There are more of those kinds of people posting stuff on the web then there will ever be of people who have some understanding of a subject. So the result is a lot of incomplete info.

GH of 150-250 ppm causes excess carbonate ions to precipitate out of the water, which stops pH from rising above 8.3. So baking soda is keeping pH from falling below 8.3 and GH is stopping the baking soda from raising pH above 8.3. Result is stable pH at 8.3. However, there are many things that affect pH so results can vary.

GH can be raised by adding say a pound of calcium chloride flake (from hardware store for deicing, 77% calcium chloride, or swimming pool supply) per 1000 gals. And say a pound of Epsom salt per 1000 gals to add magnesium. Water test to confirm results. GH is not consumed like KH so generally once you get to the desired level it stays there, excluding water changes.

How much ,different are gold fish ,We have had 3" of rain in the past 3 days ,gold fish seem to be very active and happy ,have not done any water tests ,yet ,just bread this post now I am concerned,never bothered to do many tests ,in the past unless I spotted trouble ,mostly seem the goldfish have been nearly bullet proof ,eating good ,seemed to enjoy playing inthe raindrops as they formed bubbles on the surface .any advice would be ,appreciated! Carl I do not even know a lot of the terms KH GH .ph I know ,been a very lucky I guess That I have not had any major problems ,in my ignorance of all of this .

 

[Waterbug]

Most people don't test water. If the water you put into your pond has good KH and GH, as many people do, and you don't have a lot of fish for the pond size, then there would be no problem. The terms KH and GH are easy enough to learn if a person cares to.

For pH buffering, if you just measure KH and add baking soda as needed or if needed, you will have reduced the risk of fish loss a great deal because pH will stay in the 8 to 9 range. That's way better than low KH and having pH swing between 5 and 12. The GH step is just a little extra stability, but isn't required.

 

[multifasited]

Most people don't test water. If the water you put into your pond has good KH and GH, as many people do, and you don't have a lot of fish for the pond size, then there would be no problem. The terms KH and GH are easy enough to learn if a person cares to.

For pH buffering, if you just measure KH and add baking soda as needed or if needed, you will have reduced the risk of fish loss a great deal because pH will stay in the 8 to 9 range. That's way better than low KH and having pH swing between 5 and 12. The GH step is just a little extra stability, but isn't required.

Are we talking water hardness ,still don't know what Kh and gh stand for .I am afraid ,I have more then the recommended number of fish ,over 100 4-5 " feeder goldfish ,you have seen my pond ,and layout .thanks,Carl

 

[CountryEscape]

Yikes, Multi, if you have that many now (did I read correctly on your profile, you have them in a 13,000 gal 24' round pool?) just think how many you are going to have next year! I had about 10 last year, put in the pond in June, biggest was maybe 5" long, and by fall I had an additional 12. They are early breeders. Good luck!
Yes, GH and KH has to do with hardness, but Waterbug is the one to listen to for descriptions. I have fairly high levels of both, and my PH is around 8.4, so guess that's perfect for both the koi and goldies.

 

[Waterbug]

Carl, there is only one way to learn what KH and GH is...Google it and read. If that's more work than you'd like then you have your answer. No point in testing water, no point in worrying about water quality, it is what it is.

 

[multifasited]

The way all you people throw those terms around ,I just thought it was something special and vital to watch for ,I'll google and at least know what you are all refering to.color me gone to goggle.Thanks ,Carl

 

[don't ask]

not necessarily throwing terms around, just that saying KH instead of (carbonate hardness) or non-carbonate hardness (GH) is simpler.

 

[j.w]

Wow that's some small print there don't ask..................you trying to mess w/ our eyes? :glassesy: