Causes for increasing PH?

[Ponch]

Did a 50% water change in my 5 gallon yesterday and tested the ph and other params today.

0ammo
0trites
10trates (normal day after a pwc cause I am currently overstocked)
7.6ph

for the last 3 months my tank ph in my has been in the low 7's. 7.1-7.4 and now it's jumped to 7.6. Tested the tap water several times in past 3 months as well and always around the same in low 7's.

I've just set aside some tap water to test tonight and then in the morning so I can compare to the tank ph reading....

Inside a tank what could be the possible reasons for rising Ph?

I bet a nickel the chemistry of the tap water (which is city water) is changing. If that is the case, how do others handle that? A changing Ph can't be good for the fish I imagine. (5 neons and 2 baby mollies).

Im goin to get an api water hardness test kit and drill a little deeper . Thoughts?

 

[jlk]

Lets see how your tap looks tommorrow. My city water is always fluctuating so i wouldnt be surprised if this is the culprit! It makes things a bit frustrating at times though...

 

[Ponch]

Lets see how your tap looks tommorrow. My city water is always fluctuating so i wouldnt be surprised if this is the culprit! It makes things a bit frustrating at times though...

Frustrating and concerning for well-being of the fish too! interesting that this happens to you too. Will report back tomorrow with tap PH reading...

 

[jlk]

Sounds good!

 

[LyndaB]

What substrate are you using?

I found that using play sand versus pool filter sand raised my pH.

 

[Ponch]

What substrate are you using?

I found that using play sand versus pool filter sand raised my pH.

In the 5G it's just gravel. I have a new tank I am in process of setting up that has sand (super naturals aquarium sand brand) and right now shows similar Ph reading. Will keep an eye on both to see if substrate may play a role in Ph chamges but right now that does not appear to be the case

 

[jlk]

I doubt the substrate is the issue here especially because this tank has been set up for a couple of months now. I really suspect the city water because i deal with similar issues.

 

[aqua_chem]

Some gravel is coated with a sealant to keep it from leeching. After awhile it can wear off and start leeching. I had a tank get up to 8.2 because of that once.

 

[meegosh]

I think the water is to blame here. The pH will raise and fall with the seasons. More rain/snow melt etc in some seasons than others. All these things play a factor into our water quality.

Have you tested your tap water right out of the tap, and then retest it after it has sat out for 24 hours? You will see a difference just from it degassing.

 

[richardh]

The only time I've seen my ph rise is when nitrite has risen. If you have an established tank, then the likely cause is your water source.

 

[Ponch]

Below are the latest water parameters for both my tanks-seems that Ph is actually now *dropping* in both cases.

Also note that on Dec 30th i ran ph tests on tap water left out overnight vs straight out of the tap. tap left overnight tested at 7.6 ph and water straight out of the tap tested at 6.8 ph. Are ph increases after 24 hours of settling normal?

If so, what does that say/mean for my tanks which are now showing ph dropping?

Tank 1 - established/cycled 5 gallon with fish (5 neons,2 baby mollies)
Date,ammo,nitrite,nitrate,ph
1224,0,0,10,7.4
1226,0,0,30,7.4
1228,PWC 50%
1229,0,0,10,7.6
1230,0,0,10,7.2
1231,0,0,20,6.9


Tank 2 - new 26 gallon fish-less cycling
Date,ammo,nitrite,nitrate,ph
1229,0,d,d,7.6
1230,3,0,0,7.6 (am read)
1230,2,1,2,7.6 (pm read)
1231,2,5,5,7.6 (am read)
1231,1,5,10,7.4 (pm read)
NOTE-added AngelsPlus BB "seeded" filter afternoon of 12/29 ,and dose ammo to 3ppm w/100 drops pure ammonia

I hear ph swings during cycling are to be expected to some extent which *might* explain tank 2 dropping ph but what about the swings I am seeing in my established tank - tank #1?

Thanks for insight and help.

 

[librarygirl]

You could have soft water that's low on buffers and as the fish use up the minerals in the water it causes the PH to drop. You can either do smaller water changes more often (2-3x per week) to keep the PH steady or try adding a pinch of crushed coral or crushed argonite into a mesh media bag or clean nylon stocking and add it to your filter. You won't need much at all. Most pet/fish stores sell it in the saltwater section although unfortunately they only sell larger bags which will last you forever lol.

 

[BillD]

If the pH goes up after sitting overnight the most likely cause is out gassing of CO2. It really makes no difference that you have a minor difference in pH, since the basic water hasn't changed. nitrification will cause changes in pH over time, but again, nothing to be concerned about. It has been many years since I tested for pH, as I consider it a non issue for the majority of fish we keep.

 

[Ponch]

You could have soft water that's low on buffers and as the fish use up the minerals in the water it causes the PH to drop. You can either do smaller water changes more often (2-3x per week) to keep the PH steady or try adding a pinch of crushed coral or crushed argonite into a mesh media bag or clean nylon stocking and add it to your filter. You won't need much at all. Most pet/fish stores sell it in the saltwater section although unfortunately they only sell larger bags which will last you forever lol.

Just placed half of a mesh bag of crush coral into my filter. Will see how quickly it stabilizes

 

[Ponch]

Just placed half of a mesh bag of crush coral into my filter. Will see how quickly it stabilizes

Ph is now back up to 7.6 in the tank which I am cycling... Which is a level that I'm happy at.

This morning prior to adding the crushed coral the ph in the tank i am cycling dropped to 6.6. I panicked and did a 90% water change since I did not want my cycle to stall . After the PWC the ph was still 6.6! So I again panicked and added the crushed coral. Will see what transpires but so far so good.

 

[jlk]

7.6 looks good! Lets see how this works out for you & i will hope for the best!