Low kH, low pH, best way to stabilise

[Cate45]

Hi folks

Question here is how to adjust (or whether I need to be concerned about) my low pH and low kH/GH water.

I live rurally, hence my water is all rainwater. It comes in at a pH of 6.0, and remains so after aging. The kH is 20 ppm, and although I don't have an up to date GH reading (run out of test kit) I know that is very low too. TDS is zero. The tanks are always at pH of 6.0 as well - no swings.

I do 30% to 50% WC each day, on all tanks (husband is a fish widower) and I use Seachem Replenish to add some minerals back in, at the rate of 5ml per 20 litres. Am in the process of making this stuff myself, which at least is cheaper.

So. I do remineralise, but should I also look at providing some sort of non-pH affecting buffer? And if so, what?

Thanks for any help/suggestions :)

[LJSmith]

I use crushed oyster shells in my filters. You can get them at any feed store. They use them for chickens. I have similar parameters and it helped buffer pH. I threw some in a piece of pantyhose. Cheap and effective.

[HarryDk]

I would use crushed coral, but there is a formular mix too

http://forum.simplydiscus.com/archive/index.php/t-21166.html

[Cate45]

Thanks Lucas - won't that raise the pH though? I'd like to avoid that if possible. If I've got my understanding of the process wrong, though, and buffering kH will indeed raise pH, please correct me.

[two utes]

Hi Catherine
You can afford to go higher on your pH. I maintain mine at 6.4 and as others have suggested crushed coral or shell grit in a piece of stocking in your filter will do the trick

[Cate45]

Thanks Joe. Yep, I know I can go higher; I wanted to avoid this though as that means adjusting prep water at each WC.
In the process of setting up the big tank, which I'm going to do on a drip exchange, so shouldn't be an issue then. However, at the moment, a bit more of a problem. But I'll look into it, thanks all.

[bluelagoon]

If you raise the KH the PH will also raise.They work hand and hand.Rainwater does not have bicarbonates in it and when added it will go up in KH,Ph and even GH.You cannot buffer without raising PH too.

[LJSmith]

I use maybe a cup of oyster shells per 50 gallons. I have not observed much in the way of an elevated pH and don’t do anything to adjust my tap and the fish could care less. I do about 60% WC every 3 days for my adult discus. If I use my aging barrel I would use the same ratio as the tanks.

[Cate45]

Wonderful, thanks everyone, you've cleared up my uncertainty around this and given me a way forward. Appreciate all the replies.

[sayid]

I have put a handful of normal sea shells ( stuff that you find on the beach ) in a ladies stockings and place it in the tank or canister and top it up once a year .

[Cate45]

Thank you everyone. I have access to all the things suggested, and will start some careful experiments. Finally got hold of a pH meter, calibrated it, and now I need stiff whiskey - my pH, after 24 hours standing, is 4.65. (!!) I'm surprised everyone hasn't melted.

[Cosmo]

If you raise the KH the PH will also raise.They work hand and hand.Rainwater does not have bicarbonates in it and when added it will go up in KH,Ph and even GH.You cannot buffer without raising PH too.

Correct, they go hand in hand. If you are re-mineralizing the TDS should not stay at zero, something wrong there. When I used 100% RO water (which your source sounds like) I always used Kent Ph Stable to add Kh. I never used the shells because it's difficult to measure what you need to get where you want to go. With Ph Stable that is not the case. Inexpensive and lasts a long time. Super soft water is usually very unstable so keep an eye out for Ph crashes. Ph Stable needs to be added prior to doing the water change, and should be given several hours to establish itself evenly throughout the water, it is VERY concentrated so a small amount is all that should be needed. Do not add it directly to your tank as it will kill your fish. If you are being successful now, I'd leave the water alone but closely monitor, Ph 6.0 is no problem for Discus and they love soft water - the drip system should help with stability.



I have put a handful of normal sea shells ( stuff that you find on the beach ) in a ladies stockings and place it in the tank or canister and top it up once a year .
Hopefully they are from a freshwater lake and not a salt water one.

[sayid]

Correct, they go hand in hand. If you are re-mineralizing the TDS should not stay at zero, something wrong there. When I used 100% RO water (which your source sounds like) I always used Kent Ph Stable to add Kh. I never used the shells because it's difficult to measure what you need to get where you want to go. With Ph Stable that is not the case. Inexpensive and lasts a long time. Super soft water is usually very unstable so keep an eye out for Ph crashes. Ph Stable needs to be added prior to doing the water change, and should be given several hours to establish itself evenly throughout the water, it is VERY concentrated so a small amount is all that should be needed. Do not add it directly to your tank as it will kill your fish. If you are being successful now, I'd leave the water alone but closely monitor, Ph 6.0 is no problem for Discus and they love soft water - the drip system should help with stability.



Hopefully they are from a freshwater lake and not a salt water one.

You got me thinking , i have no idea if they are from fresh water lake or salt water ,i was under the impression that they are calcium carbonate regardless of where they come from ,i think they are from salt water the same as coral pieces .

[Megalodon]

It shouldn't matter if the shells are from fresh or saltwater. The main complaint I hear against using calcium carbonate is that it's slow to dissolve so you need a lot of it. I use potassium bicarbonate myself. It's cheap and dissolves very quickly.

[two utes]

It shouldn't matter if the shells are from fresh or saltwater. The main complaint I hear against using calcium carbonate is that it's slow to dissolve so you need a lot of it. I use potassium bicarbonate myself. It's cheap and dissolves very quickly.


That's the whole idea behind using shell grit...in a sock in with your filter medium..lasts for months