Normal PH but low Alkalinity.

[gglemons]

Our pond is 3 weeks old. all tests are "normal" such as 7.2ph, however the total Alkalinity test is 40ppm. OF course ideally this should be 120-180 for Koi. Everywhere I search, each time I read about adding bicarb soda to raise Alkalinity it indicates it will raise the ph. So what gives? If the ph is the key to perfect alkalinity, why confuse all the test kits with ppm Alkalinity readings? We would like to raise it from 40 to 120 but should we bother if this means it will screw up the ph and we chase out tail?

 

[cas]

KH (Carbonate hardness) (Total Alkalinity) is needed to keep pH stable. pH swings can cause fish deaths. Yes, adding baking soda will raise the pH to 8.3, but it will be a steady 8.3.

 

[WaterGardener]

The pH number is not what is important. But the stability of pH is critical. So don't worry about trying to keep the pH at someone's idea of the perfect pH.

Raise the KH to keep the pH steady.

I've never heard that pH is the key to perfect alkalinity. Can you please explain that concept?

I keep the KH in my pond around 200 or higher. My filters work best that way.

Also, as your pond goes through the nitrogen cycle, it will produce acid, using that alkalinity, so that will fall. Rain also tends to be acidic, so alkalinity needs periodic boosting to keep it high enough to prevent a pH crash.

 

[Mmathis]

Hello and welcome!

So the term “total alkalinity” is the same as KH (carbonate hardness)? Learned something new — chemistry is not my thing, but I do understand about KH and it’s relationship to pH levels.

Something I haven’t seen mentioned in a while…..is adding something like crushed oyster shells to raise the KH. It’s not an instant fix, but it lasts longer over time — vs adding baking soda. My KH tends to be low, so I add the oyster shells mixed in with my bog media. A more consistent release.

 

[gglemons]

The pH number is not what is important. But the stability of pH is critical. So don't worry about trying to keep the pH at someone's idea of the perfect pH.

Raise the KH to keep the pH steady.

I've never heard that pH is the key to perfect alkalinity. Can you please explain that concept?

I keep the KH in my pond around 200 or higher. My filters work best that way.

Also, as your pond goes through the nitrogen cycle, it will produce acid, using that alkalinity, so that will fall. Rain also tends to be acidic, so alkalinity needs periodic boosting to keep it high enough to prevent a pH crash.

thank you (and @cas) classic is to now read up on KH, soft and hard water rather than than the word Total Alkalinity. Your advice is spot on from what we now researched. The rate of the change was a worry but found this Jap site that explained great detail https://www.mankysanke.co.uk/html/alkalinity.html Down here in Oz we have soft water of 50. Adding sodium in 4 parts over 4 days seems the way to go so we can reach 120 or so but will take it easy. Our new Koi came from a place 150 kil away and an aged old pond breeder so this maybe why they are in shock and haven't eaten for 10 days now and sizes are 2 inches to 15 inches.

We'll update in 4 days and hope there are other new koi parents that learn from all this watergardner, cheers.

 

[j.w]

@gglemons

 

[Mgessert]

What are your ammonia, nitrite, and nitrate readings please?

 

[gglemons]

What are your ammonia, nitrite, and nitrate readings please?

sorry for delay. I have to get a test kit for that, I was using my spa pool strips which have many similar quality tests. I have been adding Bicarb every day for 5 days which has slowly increased the alkaline to 120 so its much better but I am on the 8.2 ph now so cant add more.

 

[WaterGardener]

The pH shouldn't rise any more, no matter how much more baking soda you add. At most it should max out at 8.3.

I add 8 cups at a time and my pH stays at 8.2 to 8.3. The alkalinity is kept around 200 and I've boosted it to 300 when expecting heavy rain.

Also 8.2 is not a maximum safe pH for goldfish. They can live in even higher pH levels.

Unless you have some very unusual water, it won't go above 8.3 with any amount of baking soda added.

Please do get some liquid testing kits, not strips. The kits will help you know what the conditions of your pond water actually are.

 

[gglemons]

The pH shouldn't rise any more, no matter how much more baking soda you add. At most it should max out at 8.3.

I add 8 cups at a time and my pH stays at 8.2 to 8.3. The alkalinity is kept around 200 and I've boosted it to 300 when expecting heavy rain.

Also 8.2 is not a maximum safe pH for goldfish. They can live in even higher pH levels.

Unless you have some very unusual water, it won't go above 8.3 with any amount of baking soda added.

Please do get some liquid testing kits, not strips. The kits will help you know what the conditions of your pond water actually are.

just ordered the strips before i read your advice. I agree the strips are open to comparative interpretation sometimes. I like the idea to boost it to 200 so will keep adding and we are dealing with La Nina weather and are expecting heavy rain during late Autumn Spring. Some of the little Koi we've had for 16 days still haven't eaten, the bigger ones are picking a little bit now.

 

[addy1]

Our well water is very soft, can't even get a reading. And very acidic. I added bags of crushed oyster shells to the pond (via putting in the bog) after a few years the hardness has stabilized a bit above 150, last time I tested years ago. PH sits around 7.6in the pond. The well reading is 5.3