KH and PH Balance

[LibraKoi]

Hello,

I am looking for help, a tutor in the KH, PH connection. The last few yrs. I have been using crushed oyster shells in bags to try and balance my KH. The most I have been able to get it to is 2-3 drops. My pond is 3000 gals. This year I have yet to put any shells in. I was hoping to find a different, better way. It is an eyesore to find room for the shells. I use a drain sock bag and tie it at both ends and put them in my filter and waterfall shelves. They are very bulky and redirect the water flow.

I have heard that if I use baking soda, it would be a daily testing and addition of the BS, especially in the summer time. I am trying to prevent PH crash, so this didn't sound that appealing to me. Someone else mentioned Lime Powder, but I have never heard that before. If lime can be used, why can't I just go buy a slab of limestone and toss it into my pond?

Is anyone willing to work with me to get over this hump? I would like someone to stay with me so that I know I get it.

What is the best method to regulate and keep KH stable?

Please ask any questions that may help.

 

[MitchM]

This doesn't sound like it's too difficult a problem to solve.
A few questions:
What is the current KH, GH of pond water and of the source water?
What is a morning and evening PH reading of the pond water?
Do you perform any water changes, if so, how much/how often?

Limestone could be a good solution for you; baking soda doesn't have to be added and tested daily unless you will be adding more than 20ppm alkalinity value per day.

 

[LibraKoi]

This doesn't sound like it's too difficult a problem to solve.
A few questions:
What is the current KH, GH of pond water and of the source water?
What is a morning and evening PH reading of the pond water?
Do you perform any water changes, if so, how much/how often?

Limestone could be a good solution for you; baking soda doesn't have to be added and tested daily unless you will be adding more than 20ppm alkalinity value per day.

Hi Mitch, Thank you so much for responding. Here are the ans. to most of your questions.

Please note that I have not done any water changes this season since I opened the pond about 4 weeks ago. I generally don't stir things up to much for a month. I was planning on doing a 20% or more water change this weekend. I am starting to get foam, so think I will rinse my filter pads in some pond water also. As for the GH I have never been able to get a true reading on that. When I put the 1st. drop in it looks clear to me. As I move forward it only becomes more yellow and brighter. This afternoon I did 15 drops in the pond water tube, only to keep a bright yellow. In the Source water I went to 20 drops but got the same results. Is there another way to test this or should I just keep going to see if it will turn green. It is not orange, but yellow like the ammonia test color. I checked Ph. at 12 noon, 7:15 pm and will check it early morning also. I generally do a 10-15% water change every other week or once a month. In between I will top off as needed.

Are you still thinking it's not too difficult a problem? What would be my next step? It seems that since I haven't done a water change this season that my KH is 3-4 drops from last season and when I do a water change it will go down as the source water is only at 1 drop. Also I have not been able to get plants to grow--namely my floaters, I just read that the GH should be a certain amount for plants to grow. So I am assuming that my GH is below the test kit readings and that is why it doesn't seem to work right? But I really don't know. That's why I'm seeking help for this issue. So I can finally learn about that part of ponding.

Pond Source
Current KH 3-4 Drops 1 Drop

GH: Never got to green. 15 " 22 "

PH At 12 pm 7.8
At 7:15 pm 8.0

Thank you so much

 

[MitchM]

Thanks LibraKoi.
I have a high GH reading here as well, my GH testing doesn't change colour until 24 drops or more.
In this case, limestone would not be a good idea for your pond because limestone also raises GH. I think baking soda is what you should be using.
With your PH at the 7.8 level, the oyster shells won't be very effective either because they don't start dissolving until the 7.0 PH level or below. Limestone will dissolve at PH levels up to about 8.3.

Basically, you can think of KH and GH like bookends for PH. KH keeps PH from dropping too low and GH keeps PH from going too high.
You need a balance of organic material (nitrogen and humic substances), KH, GH and mineral trace elements in a pond so the pond inhabitants have all the required nutrients in order to complete their life cycle and functions. Organic matter will make up the proteins, KH is the carbonate required to neutralize acids that are produced, GH is the calcium and magnesium required for fish bone and scale development, trace elements such as iron and phosphorous that are needed for plant growth.

The above is a bit of a simplification because different organisms require different levels of the various items I mentioned, but as long as you keep your water well filtered, circulated, oxygenated, the KH and GH levels within recommended levels and feed quality food, your pond will do well.

You're only really missing a proper level of carbonates by the sound of it.

I don't think water changes are necessary unless there is a specific reason. Others disagree, which is fine. Your pond looks pretty good doing what you're doing. With your source water so low in KH, you'll need to add baking soda more often.

As far as the plants go, PH levels will affect how well plants can take up the nutrients they require. You could have available all the nutrients they require, but if you have a higher PH than the plant's natural environment would have, that plant species will starve.

Your pond currently has a KH level of about 53 ppm and you should raise it to about to at least 100 - 120 ppm which is about 5 cups of baking soda.
You could safely add 1 cup per day for 5 days for your size pond. That will raise your KH by 20 ppm per day. You don't want to add more than that because the fish need to be able to adjust to the change.
With your relatively small PH swings during the day, despite having a low KH level, I think you have a fairly clean pond. Once you add the required baking soda, you probably won't need to test your water more than once per month.

(I've got to leave, so I haven't checked over my calculations, but you are fine to add one cup of baking soda right away. I'll go over this again in the morning.)

 

[Mmathis]

You said that you put the bags of shells in the water. Be sure they are in an area of active flow.

 

[MitchM]

My calculations are about right. Check after each day you add the baking soda until you reach about the 6 or 7 drops level.

You said that you put the bags of shells in the water. Be sure they are in an area of active flow.

Even in strong flowing water, if the PH is too high, the oyster shells won't dissolve.

.

 

[LibraKoi]

Thanks LibraKoi.
I have a high GH reading here as well, my GH testing doesn't change colour until 24 drops or more.
In this case, limestone would not be a good idea for your pond because limestone also raises GH. I think baking soda is what you should be using.
With your PH at the 7.8 level, the oyster shells won't be very effective either because they don't start dissolving until the 7.0 PH level or below. Limestone will dissolve at PH levels up to about 8.3.

Basically, you can think of KH and GH like bookends for PH. KH keeps PH from dropping too low and GH keeps PH from going too high.
You need a balance of organic material (nitrogen and humic substances), KH, GH and mineral trace elements in a pond so the pond inhabitants have all the required nutrients in order to complete their life cycle and functions. Organic matter will make up the proteins, KH is the carbonate required to neutralize acids that are produced, GH is the calcium and magnesium required for fish bone and scale development, trace elements such as iron and phosphorous that are needed for plant growth.

The above is a bit of a simplification because different organisms require different levels of the various items I mentioned, but as long as you keep your water well filtered, circulated, oxygenated, the KH and GH levels within recommended levels and feed quality food, your pond will do well.

You're only really missing a proper level of carbonates by the sound of it.

I don't think water changes are necessary unless there is a specific reason. Others disagree, which is fine. Your pond looks pretty good doing what you're doing. With your source water so low in KH, you'll need to add baking soda more often.

As far as the plants go, PH levels will affect how well plants can take up the nutrients they require. You could have available all the nutrients they require, but if you have a higher PH than the plant's natural environment would have, that plant species will starve.

Your pond currently has a KH level of about 53 ppm and you should raise it to about to at least 100 - 120 ppm which is about 5 cups of baking soda.
You could safely add 1 cup per day for 5 days for your size pond. That will raise your KH by 20 ppm per day. You don't want to add more than that because the fish need to be able to adjust to the change.
With your relatively small PH swings during the day, despite having a low KH level, I think you have a fairly clean pond. Once you add the required baking soda, you probably won't need to test your water more than once per month.

(I've got to leave, so I haven't checked over my calculations, but you are fine to add one cup of baking soda right away. I'll go over this again in the morning.)

Hi Mitch, Thank you for that clarification. I tested more today, will give you those in a few. I have a question regarding the KH of my tap and the KH of my pond.

If my KH is currently at 4 drops and my tap is 1 drop, what has raised it in the last season? I did water changes last season. I tested the PH of the tap also and it is at 8 so my PH is basically what my source PH is.

I tried to get a reading on my GH and became very frustrated at 75 drops and gave up. . It went from clear to yellow and didn't turn orange until @ 45 drops where it never changed to green. I even asked on Facebook if anyone knew if we had hard or soft water--nothing but send your water to a lab. lol I am going to call the Water Dept Monday, cause now it is driving me nuts that I don't know and can't find out.

I really should do a vacuum as I have a lot of sludge on the bottom from the winter. And I have foam starting. The water is not overly clear this week as algae is taking over and I think my UV light needs a bulb. So if plants can't get enough food with high PH, how do I get that bal. even if I start to add baking soda? I usually add floaters, but the last 3 yrs. they just brown up and wither.

What else could I add to keep the Nitrates at bay?

Here are the test results.

KH 4 drops
PH @ 8 am, 8., @ 12 pm 8.
Ammonia 0
Nitrite 0
Nitrate 80-90
Phosphate 4

I would like to get the Nitrates and Phosphates lower. That will be hard if plants won't grow. Yes?

Thank you

 

[LibraKoi]

You said that you put the bags of shells in the water. Be sure they are in an area of active flow.

Hi, yes I usually put them in small bags in the filter and waterfall. But they are an eyesore and take from the water flow. I was wondering if they had bigger ones or bigger rocks of other kinds that I could use as my water fall stones that may help. It doesn't look like it though

 

[MitchM]

Can you confirm that your test kits are up to date and that you are shaking the bottles before testing?
Do you have any garden soil in your pond? Is there any garden soil dust that can be blowing into your pond?

I have 2 large indoor aquariums in my home that I supply with reverse osmosis water only (0 KH) and both aquariums register a KH of 6 and 7. There are minerals in the substrate that contribute to the available minerals in the aquarium water.

Are you on a municipal water supply? Usually they have water test results available on their website.

High nitrates and phosphate levels will contribute to plant growth. Nitrates contribute to green leaf growth, phosphates contribute towards flowering and root growth.
Excess amounts can cause excess nuisance algae growth.

 

[LibraKoi]

Can you confirm that your test kits are up to date and that you are shaking the bottles before testing?
Do you have any garden soil in your pond? Is there any garden soil dust that can be blowing into your pond?

I have 2 large indoor aquariums in my home that I supply with reverse osmosis water only (0 KH) and both aquariums register a KH of 6 and 7. There are minerals in the substrate that contribute to the available minerals in the aquarium water.

Are you on a municipal water supply? Usually they have water test results available on their website.

High nitrates and phosphate levels will contribute to plant growth. Nitrates contribute to green leaf growth, phosphates contribute towards flowering and root growth.
Excess amounts can cause excess nuisance algae growth.

My kits expire this year--some last month. I will get new ones and re-check everything. I figured they were good for a bit after the date. I do shake them before though.

Do you mean reg. ground dirt or top soil from the bag? The only soil in there is pond planting soil when I replanted a plant that was dying. The cat o nine tails are just stuck in between rocks. No soil. There is dirt that may get in on occasion, but nothing consistent. What would this do?

What minerals make up to achieve your KH of 6 to 7 in your aquariums?

I am on City water and will call them Monday to see what the values are, website was unclear.

So do you think my Nitrate and Phosphate levels are fine? Do you see anything that has been preventing the floaters from growing and thriving? When we fist opened the pond for a couple yrs. they went nuts the last few yrs., we can't get them to do anything. See photos. First 4 are from 3 yrs. ago when they would grow--last 2 are from last yr., all brown. Water was the same it is now.

If I just add the baking soda, my PH will rise a bit. So will the plants grow less? Should I add soil?

 

[MitchM]

Expired kits or kits that have sat for a long time could give readings that are very different.
Perhaps don't make any changes to your pond, other than cleaning, until we are sure we have accurate numbers.
I'll be interested to see what your municipality lists for it's water parameters.
The inability to get a GH reading was a red flag.

Lime or bone meal in the substrate may be a contributor to the rise in my aquarium's KH numbers.
My fish and plants appear healthy so I'm not too concerned about it.

One of our other members, @koiguy1969 , posted this thread about API test kit expiry dates:
https://www.fishlore.com/aquariumfi...or-api-freshwater-master-test-kit-users.6439/

 

[MitchM]

If you want to try some water hyacinth or water lettuce again, maybe try keeping them in a tub with some Miracle Grow. As they multiply, you can transfer the excess plants over to your main pond.
I think @sissy and @Mucky_Waters have done that sucessfully.
I'll have to try and find those threads.
There may not be enough nutrients for your floating plants.

 

[cas]

the oyster shells won't be very effective either because they don't start dissolving until the 7.0 PH level or below. Limestone will dissolve at PH levels up to about 8.3.

Good to know.

 

[LibraKoi]

Expired kits or kits that have sat for a long time could give readings that are very different.
Perhaps don't make any changes to your pond, other than cleaning, until we are sure we have accurate numbers.
I'll be interested to see what your municipality lists for it's water parameters.
The inability to get a GH reading was a red flag.

Lime or bone meal in the substrate may be a contributor to the rise in my aquarium's KH numbers.
My fish and plants appear healthy so I'm not too concerned about it.

One of our other members, @koiguy1969 , posted this thread about API test kit expiry dates:
https://www.fishlore.com/aquariumfi...or-api-freshwater-master-test-kit-users.6439/

Mitch, thanks for that information about the kits. I've got some ordered.

I just got off the phone with Water Treatment and this is what I was told.

GH 30-35 parts per million
KH 28-29
PH 7.6-7.8
Phosphate 21/2- 3

So she said we have soft water. Does that change anything? She mentioned if I use lime, she thinks it raises PH, but they don't use it, so she wasn't sure.

I did a small vacuum yesterday, but it was stirring up and I couldn't see, so I tapped it off. Also want to get a meter for my hose. Do you use one?

Thank You

 

[Lisak1]

This is a great thread! I'm not a water tester myself, but this has helped me so much to understand the relationship between KH, GH, and PH. When people post about it I'm like . Now I'll be able to follow along!

I did want to add for @LibraKoi - I have mixed results with my floaters from year to year. Sometimes they do great in the pond, other years not so much. They ALWAYS do well in my pondless waterfall, which is the exact same water (minus fish) so I suspect some years my fish eat the roots and other years they just aren't interested. Who knows why - maybe they feel they got too fat over winter one year and need to add more greens to their diet? haha! Anyway, last year I put them in the big pond in spots where the fish were less likely to get to them and once again they did great. This may or may not be helpful to you but I thought I would add it just in case!