Raise Kh Without Affecting Ph

[sharkbutter]

I have a 29 gallon tank. I have always had trouble with kH being low (2dh or so). My pH hangs around 7 which is super neat and I would like to keep it that way. Adding sodium bicarbonate will raise the pH to 8.2 or so and that seems high for my topical freshwater fish. They normally tolerate 6.5 - 7.5 if I have all my facts correct. Is there a way to muck about with only kH and not pH?

Thanks!

 

[ellena]

Why do you want to raise kH? Generally soft water is ideal for a lot of tropicals.

 

[sharkbutter]

Why do you want to raise kH? Generally soft water is ideal for a lot of tropicals.

I was under the impression that kH is a buffering agent forr pH levels and I wondered if some of my recent tank ills were because of rapidly fluctuating pH levels....right? Raising kH can help to stabilize pH levels. gH has to do with soft/hard water while kH is more of a buffer for pH. I do have a reasonable level of gH in my water, soft enough for tropicals.

 

[meguro]

do u have any reason to believe ur pH is actually fluctuating though?

 

[sharkbutter]

do u have any reason to believe ur pH is actually fluctuating though?

I suppose I have not tested as frequently as I might for it, I generally get around to it once every week or so. Everything I have ever read though suggests that I should keep a good buffer in my tank to avoid random fluctuations. When I do test it is usually within normal parameters . I assumed that I needed to keep a buffer to prevent instead of treat fluctuating pH levels. Am I wrong?

 

[meguro]

if nothing exists that would cause fluctuation, what exactly would u be preventing?

edit: perhaps u should elaborate more on your "recent tank ills". it might not be related to pH at all

 

[ellena]

I agree, problems you've had could be down to any number of causes. Mucking about with parameters and adding chemicals isn't the best first step.
In a fishless cycle when your bacteria are handling a very high ammonia load to build up the colony, water with a low kH can't buffer the acidic nitrates which are the end result of the cycle. Then you get a pH crash as the buffer runs out and nitrates build up.
Once you've got the fish in though and levels are much lower, the weekly water change is enough to remove nitrates before they become a problem, so pH normally stays around the same.
So, any more details on the problem you've been having? Do you have stats for ammonia, nitrite, nitrate? How big's the tank, how long's it been running, what's in it?

 

[sharkbutter]

I agree, problems you've had could be down to any number of causes. Mucking about with parameters and adding chemicals isn't the best first step.
In a fishless cycle when your bacteria are handling a very high ammonia load to build up the colony, water with a low kH can't buffer the acidic nitrates which are the end result of the cycle. Then you get a pH crash as the buffer runs out and nitrates build up.
Once you've got the fish in though and levels are much lower, the weekly water change is enough to remove nitrates before they become a problem, so pH normally stays around the same.
So, any more details on the problem you've been having? Do you have stats for ammonia, nitrite, nitrate? How big's the tank, how long's it been running, what's in it?

I would be preventing pH fluctuation.

The tank has been up and running for about a year., Though recently I had to make an emergency filter swap because mine died hard. I did my best to put as much old media in with the new media ((upgraded to a stronger filter) and I managed to get in most of it so it wouldn't have to do a complete cycle with the poor little guys in it. So that and a stupid stupid purchase of three fish carrying Ich from the big box store (yeah, yeah, I know...you think I would learn). I treated that with a course of Methylene blue and that seems to have cleared up with minimal dead loss.

My stock now is 3 guppies, 2 marbled hatchet fish, one anchor catfish, 6 neon tetras and in a few days my last queen loach. He had some secondary issues related to the water quality from the change overof the filter and is currently in isolation (but he is better now!). I want to be sure that these issues are resolved before re stocking some schoolmates.

Parameters are as follows, as recent as Yesterday:

pH - 7
Nitrites - 0
Nitrates - 0
kH - 1 dH
gH - 0 dH
Ammonia - 0

Alright, so talking through it there are other issues than just pH levels but I guess I am a control freak sometimes. Everything I have read seems to say that I need to have at least a little kH in my tank so I assumed that it was a good idea to try to supplement the water. Let me know if there is different thinking and any resources you may know of!

 

[kelly528]

Let me say that baking soda is a very bad idea if your intention is to buffer anything... its pretty unstable and unless you are keeping close tabs and adding more baking soda whenever kH dips not a good idea!

Secondly, to the best of my knowledge it is practically impossible to buffer your pH without raising it.

If you want to to buffer your tank for some reason I suggest adding some crushed coral in a nylon stocking to your filter basket. It keeps the pH in the high 7 range and raises GH and KH by a few ppm. Every time your pH goes down the acidic quality of the water will dissolve the coral, releasing more minerals in to the water and thus raising GH KH and pH. When they are back where they used to be the now higher pH of the water will stop dissolving the coral.

 

[sharkbutter]

Secondly, to the best of my knowledge it is practically impossible to buffer your pH without raising it.

That is what I was afraid of. Well is seems like the consensus is that is is not really that big of a deal to keep the kH levels up (not an emergency anyway). The baking soda is a quick fix but by no means the best. It has a pH value of 8.2 and that is just too alkaline for what I am after.

The coral seems like a good solution to my issue, I appreciate the advice!

 

[kelly528]

Oh I just love it.... Vancouver has REALLY soft water as in 0 ppm ANYTHING which is nice for tropicals but kind of a pain sometimes. I put 2 flourish tabs in my 10g and the pH crashed down to the low 5's, plus I have goldfish which need some sort of hardness in their water to osmoregulate properly. Crushed coral is exceedingly the best way I have found to maintain equilibrium.

 

[sharkbutter]

Oh I just love it.... Vancouver has REALLY soft water as in 0 ppm ANYTHING which is nice for tropicals but kind of a pain sometimes. I put 2 flourish tabs in my 10g and the pH crashed down to the low 5's, plus I have goldfish which need some sort of hardness in their water to osmoregulate properly. Crushed coral is exceedingly the best way I have found to maintain equilibrium.

I didn't realize goldfish needed that! I will have to look into that for sure. I have two comets (rescue project, long story). Poor guys and my my soft water.

Thanks again!