Ph Question

[Weezer]

What would cause the P H to fall.I am useing crushed coral for substrate. All other chemical analyses are good. Tank has been running for about 5 weeks.i have been adding P H up once a week,during this time ive done at least 1 water change sometimes 2 a week @ 10% each time..after adding P H up i wait about 24 hours to recheck.It has been running 7.4......7.6-7.8 after ph up..if i had to guess it seems like it drops after a 10% water change,but that seems like alot..I am going by the directions on the p h up bottle....Thanks...........:huh:

 

[J double R]

do you have driftwood?

 

[Weezer]

Yes.........

 

[J double R]

driftwood has tannic acid, which will naturally lower the pH in your water. if youre using crushed coral for substrate and driftwood as a decoration, your pH is probably swinging all over the place, and adding pH chemicals is not going to help. most fish won't notice a steady pH that is .5 off of their normal range.. what is your reasoning for needing a specific pH like that?

 

[Weezer]

Ive never had this happen on my other rigs...

 

[J double R]

i don't know the definite answer to your water chemistry problem, just a likely cause.
i recommend removing the driftwood.

 

[Weezer]

The type of fish require 7.8-8.2 acording to the charts i looked at....Thanks for your help..

 

[J double R]

sorry for not elaborating. the crushed coral is a good thing, that will help your buffer and whatnot, the driftwood is what's killing you, by lowering the pH against the buffer.

 

[Weezer]

i under stood your reply..i ll have to watch it closely,you had asked why a certain ph range.and i responed in a previous post.....

 

[liv2padl]

messing about with your water chemistry in order to achieve a pH difference of 0.2-0.4 makes absolutely no sense. moreover, without knowing anything about your water chemistry with regard to kH, you have almost zero chance of being successful. the fact that you've not had the same "trouble" with your other rig(s) is pure luck.

it's easy to figure out why you're failing here. it's a matter of your (1) inherant kH (buffer capacity), (2) the chemical in "pH up" (3) the amount of crushed coral you're using, and (4) you don't know what you're doing.

my advice is to stop playing with your pH. whatever it is out of the tap is just fine. your doing far more damage to your fish by having an unstable pH than any good you believe you're doing by changing it.

as for driftwood, yes it has tannins (tannic acid) but it's pretty much a myth that it changes your pH. most water in the US has an inherant buffer capacity which is far stronger than the very weak acidity of the wood.