Tap pH is 8 but tank was 7

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
I just tested my water and my tap waters ph is 8 but my tank's ph was 6.8 to 7. I'm really confused because my water is hard with gh of 10 and kh of 7 yet my ph fluctuates so much and kh is eaten away. I did a 50% water change and ph is 7.6-7.8 now. Anyone know why my ph was this low?
 

plecodragon

Well Known
Member
Messages
646
Reaction score
122
Experience
5 to 10 years
Do you have driftwood? The tannins in the wood can lower ph if it is leaching (turning the water yellowish).
 

TWiG87

Well Known
Member
Messages
2,354
Reaction score
2,232
Location
NJ
Experience
5 to 10 years
Do you inject CO2? Carbon dioxide will also lower ph
 
  • Thread starter
  • Thread Starter
  • #5
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
No it's a low tech moderate lighting and I use root tabs for my heavy root feeders and easy green all in one liquid fertilizer weekly.
 

Convoluted77

Active Member
Member
Messages
60
Reaction score
59
Location
Michigan
Have you tried filling up a bucket with tap water and checking the ph after it sat for 24hrs(with an airstone if possible)? Usually the opposite of your situation is the result(ph rise instead of drop) but there is some water facilities that have treatments that actually remove most of the co2 from the water.once the water is out of the tap the ph will drop as the co2 gets back in to it.Its worth a shot
 
  • Thread starter
  • Thread Starter
  • #7
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Convoluted77 said:
Have you tried filling up a bucket with tap water and checking the ph after it sat for 24hrs(with an airstone if possible)? Usually the opposite of your situation is the result(ph rise instead of drop) but there is some water facilities that have treatments that actually remove most of the co2 from the water.once the water is out of the tap the ph will drop as the co2 gets back in to it.Its worth a shot
 
  • Thread starter
  • Thread Starter
  • #8
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Sorry I accidentally sent that reply. Yeah my tap ph is 7.2 then after 24 hours its 8 so I just assume it will turn to 8 after 24 hours in the tank right?
 

Convoluted77

Active Member
Member
Messages
60
Reaction score
59
Location
Michigan
RomanNoodles96 said:
Sorry I accidentally sent that reply. Yeah my tap ph is 7.2 then after 24 hours its 8 so I just assume it will turn to 8 after 24 hours in the tank right?
Yeah most likely.The rise in ph is what most people deal with but I figured it was worth a shot as some people have a drop.I dont use tap water now but when I did it was nearly identical to yours but with around 7.6ph.i switched to ro water because it was solid as a rock and I could barely get the ph .1 lower with driftwood and catapa leaves and tannins galore.If your water parameters(nitrite ammonia nitrites) are staying good then you you can add crushed coral to your tank.It dissolves at a faster rate as your ph drops and buffs your water to around a 7.6ish ph.1lb of coral per 10 gallons does the trick and you can just add more as it dissolves away.Doesnt really answer the question you have about what exactally is eating your kh in between water changes but it's a great fail safe to use if you are happy to have a stable higher ph
 
  • Thread starter
  • Thread Starter
  • #10
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Convoluted77 said:
Yeah most likely.The rise in ph is what most people deal with but I figured it was worth a shot as some people have a drop.I dont use tap water now but when I did it was nearly identical to yours but with around 7.6ph.i switched to ro water because it was solid as a rock and I could barely get the ph .1 lower with driftwood and catapa leaves and tannins galore.If your water parameters(nitrite ammonia nitrites) are staying good then you you can add crushed coral to your tank.It dissolves at a faster rate as your ph drops and buffs your water to around a 7.6ish ph.1lb of coral per 10 gallons does the trick and you can just add more as it dissolves away.Doesnt really answer the question you have about what exactally is eating your kh in between water changes but it's a great fail safe to use if you are happy to have a stable higher ph
Yeah idk why for a good 2 weeks it was at a stable 8. Maybe because the tank is still cycling is why? Thanks for the coral tip might look into it.
 
  • Thread starter
  • Thread Starter
  • #11
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Convoluted77 said:
Yeah most likely.The rise in ph is what most people deal with but I figured it was worth a shot as some people have a drop.I dont use tap water now but when I did it was nearly identical to yours but with around 7.6ph.i switched to ro water because it was solid as a rock and I could barely get the ph .1 lower with driftwood and catapa leaves and tannins galore.If your water parameters(nitrite ammonia nitrites) are staying good then you you can add crushed coral to your tank.It dissolves at a faster rate as your ph drops and buffs your water to around a 7.6ish ph.1lb of coral per 10 gallons does the trick and you can just add more as it dissolves away.Doesnt really answer the question you have about what exactally is eating your kh in between water changes but it's a great fail safe to use if you are happy to have a stable higher ph
So I could fill a bucket with tap water a couple days before the water change and the ph would be 8 by the time the water change. Would that work?
 
  • Thread starter
  • Thread Starter
  • #15
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Chanyi said:
Whoops, let's get this straight,

Your tap water is 7.2 and tank water is 8.0?
Tap water at first comes out at 7-7.6 range and after 24 hours the ph of it is 8. My tank water currently is 7.8-8 because I did a water change around 24 hours ago so the ph of the water I added went back to 8.
 

Chanyi

Well Known
Member
Messages
907
Reaction score
976
Location
Forest City Ontario
Experience
More than 10 years
RomanNoodles96 said:
Tap water at first comes out at 7-7.6 range and after 24 hours the ph of it is 8. My tank water currently is 7.8-8 because I did a water change around 24 hours ago so the ph of the water I added went back to 8.
Okay that is normal as the CO2 off-gasses, the carboxylic acid levels reduce allowing the pH to climb to its true value. Nothing to worry about.
 
  • Thread starter
  • Thread Starter
  • #17
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Chanyi said:
Okay that is normal as the CO2 off-gasses, the carboxylic acid levels reduce allowing the pH to climb to its true value. Nothing to worry about.
Does the ph change cause stress in the fish or does it affect them?
 

Chanyi

Well Known
Member
Messages
907
Reaction score
976
Location
Forest City Ontario
Experience
More than 10 years
RomanNoodles96 said:
Does the ph change cause stress in the fish or does it affect them?
No, because there is no mineral / TDS change and no osmotic pressure change. It's simply a very weak acid dropping the pH, and then slowly raising it as the CO2 offgasses and carboxylic acid concentrations reduce.
 
  • Thread starter
  • Thread Starter
  • #19
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
Chanyi said:
No, because there is no mineral / TDS change and no osmotic pressure change. It's simply a very weak acid dropping the pH, and then slowly raising it as the CO2 offgasses and carboxylic acid concentrations reduce.
Thank you. Funny how we become almost like chemists when keeping fish.
 
  • Thread starter
  • Thread Starter
  • #20
OP
R

RomanNoodles96

Active Member
Member
Messages
94
Reaction score
12
Experience
Just started
RomanNoodles96 said:
I just tested my water and my tap waters ph is 8 but my tank's ph was 6.8 to 7. I'm really confused because my water is hard with gh of 10 and kh of 7 yet my ph fluctuates so much and kh is eaten away. I did a 50% water change and ph is 7.6-7.8 now. Anyone know why my ph was this low?
Idk if there is a proper way to do an update but I'm just gonna do it like this. After recent testing I have found that my tap water ph is 7.8 straight out of the tap. This is weird because it use to be lower but it might be because I couldnt read the test right since that was around a month ago. Kh is 6 and gh is 8. Now this is before 24 hours so I'll leave the water out to test in 24 hours. My tank water is ph is 7-7.2! I'm really confused why its so low because I have nothing that could be lowering the ph in the tank. Gh is 8 and kh is 4-5. Something might be eating away my kh but idk what. I did a 40% water change 3 days ago. If anyone can help it would be appreciated.
 

New Threads

Similar Threads

Follow FishLore!

FishLore on Social Media

Online statistics

Members online
133
Guests online
2,235
Total visitors
2,368

Aquarium Photo Contests

Aquarium Calculator

Top Bottom