Do large water changes change Ph?

[guppygirl123]

Two of my guppies died the other day. *cry* *cry*
Anyways I did a 6 gallon water change with dechlorinated tap water, like always. Only normally I do 3 gallon water changes every 3 days.... So my water looked good, tank was looking good, and I bought two new baby guppies. The next day one was dead. The people at petco tested my water and told me my Ph was 8.4!
I know it hadn't been that high before... So did the 20% water change cause my problem? I already got the Ph back down but I'm just wondering...

 

[Marinemom]

What is the normal PH in your tank? It is much better to have a stable PH then one that fluctuates up and down which can cause problems for the fish. What was the PH before the water change and what was the PH after the water change? Is there a big difference? Did you test the PH out of the tap? That may be your problem. Please do not use chemicals to adjust your PH because in the end this causes more problems then it solves. You can work with the PH that you have, you just have to make sure that it stays consistent between the tank water and the water that you use to do your water changes with.

Marinemom

 

[plah831]

water changes can result in changes in pH if you haven't done one in a long time. The buildup of wastes will make your tank water more acidic. That said, sometimes tap water supplies will change something to their additives that will also result in pH changes. Since you seem to be on a very good water change schedule (50% every few days), perhaps it is the latter?

 

[guppygirl123]

My Ph had been fairly neutral.... Maybe 7.4-7.6ish.... Sorry I can't really remember the exact number. I know my tap water has a fairly high Ph but I hadn't done a water change too long ago so I don't think the water was very dirty.
I got some of those dissolving tablets and added one in. Water seems pretty good now and all the fish are fine. I'm just glad they survived the sudden change.

 

[plah831]

Please do not use chemicals to adjust your PH because in the end this causes more problems then it solves.

I second that advice! guppygirl, you probably want to test your tap water pH as Marinemom suggests, so you can get an idea of a "baseline" or control value.

 

[CaitxSith]

did he use strips?

because my petco uses strips to test water xD

So it wasn't really a surprise when he told me that my water conditions were fine lol.

 

[wataugachicken]

strips are crap. i've heard that the best way to test the ph of tap water is to let it sit out for a few hours or overnight, that allows all the dissolved gases (that are in there from pressure in the pipes, etc,) to evaporate out and give you a better reading.

how did you acclimate your fish before releasing them into the tank? they may have been shocked going from the petstore water to the ph in your water at the time.

don't use ph-changing chemicals. . . ph is measured on a logarithmic scale, so each .1 of change (i.e. 7.1 to 7.2) is ten times more acidic (or basic) than the last reading. using chemicals and making the ph go all over the place is worse than it being high or low. however, you may want to call your local water company and see if they changed anything recently in their processing. they may have added something or changed a procedure that affected your ph readings. that kind of thing has happened before, very unexpected.

 

[SirWired]

Two of my guppies died the other day. *cry* *cry*
Anyways I did a 6 gallon water change with dechlorinated tap water, like always. Only normally I do 3 gallon water changes every 3 days.... So my water looked good, tank was looking good, and I bought two new baby guppies. The next day one was dead. The people at petco tested my water and told me my Ph was 8.4!
I know it hadn't been that high before... So did the 20% water change cause my problem? I already got the Ph back down but I'm just wondering...

You say you already got the pH back down... HOW did you get it down?

SirWired

 

[wataugachicken]

I got some of those dissolving tablets and added one in. Water seems pretty good now and all the fish are fine. I'm just glad they survived the sudden change.

chems.

 

[ROLLIN]

Since you seem to be on a very good water change schedule (50% every few days), perhaps it is the latter?

She usually does 3 gallons every 3 days on a 29, not a 6 gallon. Just thought I would point that out.