Water Changes and PH Swings

CrownMan

Junior Poster
Sep 8, 2005
17
0
1
Arlington, Texas
I recently joined up and I wish to ask a question about water changes and ph. As per Tom's recommendation on another forum, I recently added CO2 to my 30 Gallon Long (about 6 hours ago) and my ph is headed down very slowly (I have it set at about 25 bubbles per minute and will adjust if necessary). I religiously perform a 50% water change weekly and since my city water has a rather high ph (7.8), and I will be keeping my ph around 6.75 to get the desired ratio of CO2 with my KH of 4, will the rapid ph change be a problem for my fishees? If so, what would you recommend. I have 4 cardinals, a ram, 6 otos, 2 cory juliis, 3 diamond tetras and 1 female betta in my aq. By the way, is that too high a fish load in your opinion?

Thanks,

Mike Herod
 

Spar

Guru Class Expert
Jun 5, 2005
123
0
16
41
Dallas, TX
Re: Water Changes and PH Swings

fishload is fine for a 30g.

pH swings due to co2 does not phase fish negatively. you may still take it slow anyway just so they get used to the co2 in the tank, but probably not necessary.
 

bennyss

Junior Poster
Aug 5, 2005
10
0
1
Re: Water Changes and PH Swings

Hi,
In 50% water change assuming the KH of the added water are the same your PH will swing to about 7.05.
Seems to me quiet alot if done immediatly.
Regards,
Benny
 

CrownMan

Junior Poster
Sep 8, 2005
17
0
1
Arlington, Texas
Re: Water Changes and PH Swings

My PH did swing to 7.2 from 6.86 after my water change this morning and about the only thing I noticed with my fish was that they weren't eating their favorite food afterward. After I posted this question, I read the April Barr Report where ph swings were discussed for both water changes and turning off co2 at night and no fish health problems should occur with either is what I got out of it. I have read and or browsed all of the Barr reports now and that was one of my favorites.

Thanks,

Mike
 

Spar

Guru Class Expert
Jun 5, 2005
123
0
16
41
Dallas, TX
Re: Water Changes and PH Swings

bennyss said:
Hi,
In 50% water change assuming the KH of the added water are the same your PH will swing to about 7.05.
Seems to me quiet alot if done immediatly.
Regards,
Benny

most water companies add gases to the water to make the difference in pH, and have no real choice but to have that large immediate swing in pH. as long as the KH is the same, no one seems to have problems with the swing.

i.e. my tap water reads at 8.5 pH out of the tap. My planted tank is at 6.0 pH. For the first couple hours of a water change my pH is sky rocket high (as I do 75%+ water changes. Never had fish or plant health consequences.