pH, driftwood, and pwc's

LeahK

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Jul 5, 2007
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I don't know why, but it's never occurred to me before to test the pH of my tap water and compare it to what's in my tank.... Anyway, yesterday at the lfs I bought a piece of driftwood about 12" long but very thin and narrow. I boiled it for about 45 minutes before tying plants to it and putting it in the tank. There are already 2 other tiny pieces in there, which have been in there for several months.
This morning I got up and tested the water to see what effect this all might have on my pH. I tested 3 things: my current tank water, that's had the new driftwood in it for about 12 hours (about 7.5); a bucket of my old tank water, from before the addition of the new wood (also 7.5); and some de-chlorinated tap water that sat out overnight (about 8).
So my tank water's pH seems to be unaffected, but this was the first time I realized that my tap water is 8 and my tank water is 7.5. Should I worry about this when I do water changes?
I should add, I do multiple, small water changes per week. The tank is 55 gallons. Often, I change 4 gallons (or about 7%) per day. I may skip a day, but I never change more than 8 gallons (or about 14%) at one time. Are any of these changes big enough to alter the pH enough to hurt my fish?
 
Test your tap pH after it has set out in a shallow dish overnight...then compare. The ability for driftwood to dramatically alter your pH is highly over rated.
 
The tap water I tested did sit out overnight, though not in a shallow dish. It was from a gallon jug that was less than halfway full--it was the leftovers from some water I dechlorinated the day before but didn't use all of. I'll test again on some water from a better dish, but if it still comes out as 8, do you think that's cause for concern, or are my water changes small enough to make the difference in pH manageable?
 
I wouldn't even dechlor the sample..just put some in a dish like a saucer. For the fish you are keeping, I do not see any issues. What is your substrate?

I would just do 25% water changes once or twice a week.
 
That's good news. I guess I was just worried b/c I've heard that fish can die if the pH changes too quickly, but this difference b/t my tank and the tap water has probably been there all along. I'll keep an eye on it, but if I haven't had any trouble so far I don't expect this new driftwood, from what you say, will make much of a difference.
And, as you asked, my substrate is aquarium gravel.
 
Keep us updates LeahK, always willing to help!
 
.5 difference in a water change will do very very little to your tank water. Your tank should be a little lower then tap....I mean its aged water with fish and other factors adding acidity.

You will be fine.
 
Many times tank maintenance will cause a need to do large water changes(like when tanks leak or break or suddenly cycle) unexpectedly. I personally had to do one on my discus tank recently. I did about 80% change, and did not have the ability to change pH first(I use peat moss in a filter bag). There was a full point difference in water. Fish were actually happy with the new water, no losses. Lots of "lets play tag" when done. Happy, stress free, fish seem to be able to do this better than fish going through bad water problems...
 
My experience with driftwood is that it causes a slow change indeed, as already mentioned. But it will eventually help a tank stabilize at a lower pH - it just takes a lot of time. That's actually good for the fish, since it won't cause big/sudden swings in pH. Anyway, my 20g tank with a big (for this tank) piece of driftwood seems to want to stablize at 6.6, but my tap water is close to 8.0 like the OP's. When I do a w/c, I add some pH-lowering powder (I forget the brand, but it's a white powder) along with the dechlorinator before adding the new water to the tank. My goal isn't to change the pH of the tank, but rather to maintain it. So I'm trying to match the bucket of fresh water to the tank's pH. I tested this out at a couple dosage levels of the power, and it now works really well. This powder has the added benefit of pulling some calcium (or whatever it is that makes water hard) out of solution, so the new water is relatively soft. My Ram and Cardinal Tetras like that. But the big thing is not try to adjust the water in the tank, but rather get the water to match the tank's natural conditions before adding it to the tank.
 
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