I'm really struggling to get my water right on the new pond.
My ph measures 8.2 (the highest mark on the test kit) and I do the acid demand test, work out how much acid I need. I dilute this in some water and add little bits over several days, only to find at the end the ph is the same.
I don't like putting in so much acid. What must I do?

Hi Stumple Is your Koi in already?
If not, 1 liter of acid over a 24hr period and then a water change. Re check PH and repeat process if necessary.

thanks Bobby.
No, the koi are not in yet.
I've done a litre acid, (over days) and then it read that i needed another 600 ml, of which I am nearly finished and the PH is the same.
What % water change?

oh also this morning the water is a little cloudy, making me think all this acid is no good.

Use 2L followed by a 30% water change, one of our members in Cape Town used this with great success.

Mario maybe you should share your experience in getting the PH under controle with stumble.

Stumple 8.2 PH should not really be a problem.

I wont worry about it if the PH is between 8.0 and 8.5. It will come down in time. Mine was 8.5 in the beggining and stayed like that for the first year or so..currently mine is 7.5 - 8.0

What is your tap water?

Hi,

Back in 1992 I killed 400 high quality baby koi (about 20 - 25 cm) using acid to try reduce the pH. The pH was over 9. The water was pea green.

Avoid acid.

A pH of 8.2 is not a problem. Koi can live quite happily in a pH range of 7 - nearly 9 provided the daily fluctuation is not large. And that was only 5 litres of acid in 75,000 of water that was added too quickly.

Take the pH in the morning and again in the evening. If there is a large fluctuation then you need to look at the buffering capacity of your water.

Green water will affect the pH.

pH is one of the water parameters we should not fiddle with as each point change has a profound influence of the fish.

Also remember the pH of the water affects the functioning of the nitrifying bacteria in the filter. These bacteria prefer an alkaline water environment. And below pH 7 they are hardly functioning at all.

Chris

Thanks guys!!

Wayne I checked my tap water and its also 8.2.


The thing is I'm not sure if the pond water is sitting at 8.2 or even higher because the test kit I have only goes up to 8.2.
I'm still waiting for my hanna tester. that has a much wider range so I would be able to have a more accurate reading.

This morning I noticed my water looking quite milkly..?? not sure why. Could it be all the lime in the water. ? or from the acid.

Chris sorry about your fish loss.
I don't have any fish in the pond yet! Also the UV light is on, so no green water either.
Do you mean acid is bad news only if the fish are in the pond? Will it have any effect on the fish later?
I will try the morning and evening ph test tomorrow and see.
thanks for your help.

The milky water - In the Aquarist groups that is usually known as a bacterial bloom but i cant say without seeing it.

Its just natural that your pond will have water of a simular chemistry as your tap water...after a few years your pond will start to settle into its own "chemistry" where it will start to differ from your tap water slightly.

In my personal opinion the Acid that you added to the water is a waste as the PH will climb back up in the weeks to come as you clean your filters and do water changes with the water from your tap. Unless you continue to add x% acid to the new tap water as you do topups.

I know that people use acid to wash the walls of their pond prior to filling it with water to so prevent lime leaching and spiking the PH but looking at your pond PH and tap water PH i dont think you have PH spiking.

Go and read this article : softly does it
In the article is a section called "money for old rope" that covers the example of a person that wants to up his KH. The reverse of what you want to do but it comes down to the same thing.

Stumble the following obviously does not apply to you but just want to add that the only people that usually have to add bicarb to their pond water weekly or monthly are the once that (1) dont do weekly water changes, (2) whos water source has a natural low water buffering.

What happens is that the KH drops as the carbonate "buffering" is being used up in the water by the filters and koi and that cause huge PH fluctuation.

I would advise those people to rather use oyster shells as its beter in the long run.

Settle Wayne. The acid will not reduce Tap water PH, and this was not implied. My understanding is that this was to lower the PH of a new unused pond build due possible cement build up in pipes and on walls, especially if the walls was not washed down before adding water.

This method has been used successfully by many hobbyist in 2009 and also a proffered method used by Pieter on all his new ponds before adding Koi to the pond.

Sorry Bobby.

It was never mentioned that i was to be used to clean pipes ect... The question was reagrding how to lower PH and so i and chris responded that it was not needed.

Sorry again if i got to over excited again.