Looking for water chemistry advice

[dba4life]

Hi,

New to the forum. I have had a 75g freshwater aquarium going for about 15 years. However I am still a novice when it comes to water chemistry. Been lucky through the years of never having much of an issue. Currently the house has very soft well water and 6.3ph. However once it has been out of the tap for 12+ hours it jumps up to 7.5ph. We have lived here for 5 years and historically this tank has had low ph in the 6.3-6.4 range. So adding the well water in during changes never resulted in a major ph change. However as of the last year the ph has increased to 7.5 over time. Now when I add the 6.3ph water in during a 40% water change the ph drops to 6.8. 9 hours later it is back up to 7.2ph. Tomorrow it will be back to 7.5.

Data I have collected from the tank:
PH 7.5
KH 54 ppm
GH under 18 ppm
Phosphates .5ppm

Ph after 40% water change = 6.8 / 9 hours later = 7.2 / 24 hours later 7.5

Well water (from county water analysis):
ph from tapthat I am using in water changes: 6.3 / After 24 hours 7.5 (my measurement)
KH - 52 mg/l
GH - 18 mg/l
Calcium 4.9 mg/l
Magnesium 1.5 mg/l
Copper, Aresenic, Fluride, Iron, Manganese, Lead, Zinc all in very very low amounts

The only thing I am adding to the tank is Kent Ph stable before water changes to to raise the KH to buffer. I add enough to raise the kh by 40ppm.

I have a Rena Filstar XP3 canister. It has the foams, Charcoal, Biostars and currently has a phosgard pouch as the phosphates increased over the past few months and now I have them down to .5ppm.

There is also a lot of driftwood in the tank along with a very large red slate rock wall. All fake plants.

First question - Do I need to worry about the ph going down from 7.5 to 6.8 during water changes. I did one today and the fish seems totally fine. But this seems like far to large of a swing.

Second question - What should I do about it? Is there something I can add to help? Is there a way to raise KH and GH without increasing PH?

Thanks for any advice.

 

[dba4life]

Hi - Is there a better place to post this question? If so, please just let me know. Thanks.

 

[Shadowraven]

It is a moderate swing in pH, but it is over a long time. Your fish should have plenty of time to adjust to that degree of change in that amount of time. If you are really concerned about your pH going up after changes, the addition of a small amount of peat to the filter can help buffer that. But I wouldn't do that in your situation.

Unless your fish are having trouble with it, I wouldn't worry too much about it.

BTW, if that is your tank in that picture, then I am impressed. It is very beautiful. I particularly like those rocks and driftwood that are in there.

 

[severum mama]

Hm, I would try testing your well water after you have popped an airstone in it and let it sit for a while. It could be that there is CO2 gassing off and that is why the pH goes up.

 

[dba4life]

Hm, I would try testing your well water after you have popped an airstone in it and let it sit for a while. It could be that there is CO2 gassing off and that is why the pH goes up.

Is there something the airstone does versus just letting the water sit? Water comes from the tap at 6.3 and 24 hours later it goes to 7.5ph.

Thanks for the compliment ShadowRaven. That is my tank in the pict

 

[dba4life]

Tried to get a better shot without the bubbles messing with the camera

 

[Shadowraven]

Aeration not only helps keep the water column mixed in the tank, it aids in the water's absorption of O2 and release of CO2 from the water. It also aids in getting rid of other harmful gases that could be dissolved in the water. This release and exchange of gases is what changes the pH of the water in your tank.

kH, gH and pH are pretty interconnected. I don't know of any good way to raise one without affecting the other two. Carbonate rocks will raise your kH and gH, but may also raise your pH along with it. Maybe someone else will have some magic answer here, but IME affecting one will alter the others.

Your tank looks like you might have been going for a South American biotope. Is that true?

Very nice picture. I may have to make a wallpaper out of it!

 

[mandell]

I had a simmilar problem it turned out to be the water soffener downstars had to swich to R/O watere mixed with kent R/O right and sea chem's acid buffer, and alkiline buffer to set ph(directions are charted on both bottles).

You can get water some times at your local fish store or grosier(I have jewl) the water should say if its been filtered by a prosses called reverce ossmoisis