I recently filled my 75 gallon. My tap water is a 7-7.2pH. I mix 4 gallons of tap with 1 gallon R.O. in a 5 gallon jug. I'm confused because all the water I added had a pH of 6.8, but now it is reading much higher at a 7.8. I haven't added anything other than Prime to the tap water, and my decor are pots, which do not affect my pH. My tank is not cycled or anything. Like I said, I just added the water, and I don't understand how I can have this large pH swing, especially when all the water I added was at a pH of 6.8. Advice anyone?
ph spike in newly set-up freshwater aquarium. Needing advice
- Thread starter DSenn
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aqua man
Aquarium Advice Regular
you can add a ph decreaser if it persists past the cycle,but it's not a permanent fix. however the less chemicals the better. there is also certain wood that will lower ph permanently if put in, but the wood needs to soak for a whil to release the tanins. otherwise the water will turn brown. let it cycle without fish and then see where your at.
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i cant tell you why your ph jumped up but i can tell you your ph wont settle tell after you cycle. it will jump around some. dont worry to much about where your ph is after your cycle is complete, just make sure that it stays the same.
for the most part fish hate change in water parameters. so water parameters that stay constent are more important then tryng to find the ideal range.
also how did you test your tap water ph? it needs to sit for 24 hours to gas off before you can get your true ph readings. testing the water right out of the tap wont give you a true reading.
and welcome to AA you will find many many people with alot of knowlede and are willing to help.
for the most part fish hate change in water parameters. so water parameters that stay constent are more important then tryng to find the ideal range.
also how did you test your tap water ph? it needs to sit for 24 hours to gas off before you can get your true ph readings. testing the water right out of the tap wont give you a true reading.
and welcome to AA you will find many many people with alot of knowlede and are willing to help.
aqua man
Aquarium Advice Regular
i agree as long as it stays the same . however make sure you get fish that can tolerate the alkalinity
I have worked very hard at getting my pH to stay at a 6.8-7. Like I said, I have an R.O. unit just for this very reason, so I can mix my tap and the R.O. together at certain ratios, depending on where my tap is. I can see the pH rising a bit, but from a 6.8 to a 7.8 in 24 is rediculous. Even if I were to get a reading of 7 out of the tap, I doubt it would jump to a 7.8 after letting it sit for 24 hours. I understand that keeping the pH consistent is most important, but I want to keep it consistent at a 6.8-7. With my focus being tetras, I don't want to go any higher than 7.2. It's strange because I've never had this kind of spike before, and as far as I can tell, my KH and GH are unchanged.
But anywho, thanks for the advice. This forum is probably exactly what I've been looking for, as we all know this is the most humbling hobby out there. I have many questions, and hopefully I have some answers too.
But anywho, thanks for the advice. This forum is probably exactly what I've been looking for, as we all know this is the most humbling hobby out there. I have many questions, and hopefully I have some answers too.
it is possible for the ph to be that much higher during the cycle. i have a tap ph of 7.8-8.0 if i remember correctly. when i was cycling my tank it was up to 8.6 at times. now its down to 7.6 after my cycle and i have neons no problem.
Oh, and I would never mess with a pH down product. I strip that KH away with my R.O. unit and then mix it with tap to come out where I want. pH down is temporary. And I don't want to put any driftwood in this particular tank.
Might I also add that it took me 3 days to fill my tank. During this time, I would periodically test the water in the tank as I filled it. The pH remained around a 6.8 this entire time. It wasn't until the tank was totally full and after the filter was turned on that I noticed the spike. Maybe I should call Mulder and Scully for this one...
Might I also add that it took me 3 days to fill my tank. During this time, I would periodically test the water in the tank as I filled it. The pH remained around a 6.8 this entire time. It wasn't until the tank was totally full and after the filter was turned on that I noticed the spike. Maybe I should call Mulder and Scully for this one...
Wow, this forum is great. Another response already. Harmy4993, you're probably right, and I should expect some fluctuations. This hobby tends to make you a bit paranoid, especially when you work hard to get things right where you want them just to have them shift on you. My question is, if my KH has stayed the same, then how is my pH jumping so much? I thought KH kept it in place...
SpeedEuphoria
Aquarium Advice Addict
Yep hit reload, lol
You should let some tap water sit out for 24hrs and test the PH?
My tap is 7.4 out of the tap and after sitting or being in the tanks it goes to 8.0-8.2
You should let some tap water sit out for 24hrs and test the PH?
My tap is 7.4 out of the tap and after sitting or being in the tanks it goes to 8.0-8.2
and it is possible to change your ph without channging your kh. one way is thru co2. im not saying your putting co2 in your tank cause im sure your not. but co2 lowers your ph without changing your kh. thats just one example. smarter people then me will know more.
the reason i ask about your kh is most tap water has a co2 count of 3.0ppm. its possible that the ro water has change that thus effecting your ph?
the reason i ask about your kh is most tap water has a co2 count of 3.0ppm. its possible that the ro water has change that thus effecting your ph?
Fishyfanatic
Aquarium Advice Addict
I am moving this thread to the FW Getting started Forum.
Fill a glass of water and let it sit on the counter for 24 hours then test the pH. The reading coming straight from the tap is not the true readign. It needs to sit before you'll have a true reading.
*edit*
I didn't see Page 2, I agree with Speed. Mine comes out around 7.0 but after sitting out overnight it jumps into the lower 8's.
Fill a glass of water and let it sit on the counter for 24 hours then test the pH. The reading coming straight from the tap is not the true readign. It needs to sit before you'll have a true reading.
*edit*
I didn't see Page 2, I agree with Speed. Mine comes out around 7.0 but after sitting out overnight it jumps into the lower 8's.
Wow, I wake up and get all these responses. Awesome. I will try letting the tap sit out overnight, but like I said, it took me three days to fill my tank. Each day I'd test the water in the tank itself, which had already sat out for a day or two, and the pH read the same at a 6.8. It wasn't until I had it all the way filled and turned the filter on that the next day when I tested it, it read a 7.8.
I am going to let a glass of tap sit out overnight like you all recommend and test it before I go any further.
On a somewhat similar note in terms of getting a lower pH, does anyone here use a R.O. unit? If so, what kind of ratios of tap/R.O. do you use to get your pH low? I often use 2 gallons tap/3 gallons R.O. I am asking because I want a lower pH, but at the same time I don't want to drop my GH/KH too low. What is the lowest acceptable amount of GH/KH one needs in their tank?
I am going to let a glass of tap sit out overnight like you all recommend and test it before I go any further.
On a somewhat similar note in terms of getting a lower pH, does anyone here use a R.O. unit? If so, what kind of ratios of tap/R.O. do you use to get your pH low? I often use 2 gallons tap/3 gallons R.O. I am asking because I want a lower pH, but at the same time I don't want to drop my GH/KH too low. What is the lowest acceptable amount of GH/KH one needs in their tank?
rich311k
Aquarium Advice Addict
There is CO2 dissolved in tap water. CO2 is an acid, as the CO2 gasses out of the water the PH goes down.
Fishyfanatic
Aquarium Advice Addict
My pH actually increases after sitting out overnight, not decrease.
I'm just curious, but why are you wanting to lower your pH? As long as it is stable, you won't have any issues unless it is off the charts.
I'm just curious, but why are you wanting to lower your pH? As long as it is stable, you won't have any issues unless it is off the charts.
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