pH question

[spyyro]

I just checked the params in my new tank and the pH is at 7.5. This is higher than my other 29 gal tank which is currently at 7.0. I do, however, have a piece of Malaysian driftwood in the new tank (75 gal) but it is a smaller piece (approx. 7" X 4" or so... a little knot w/ a hole). Would this piece of wood cause that much of a pH difference in such a large tank? I don't think the rise in pH is bad but just wondering. All my other params are perfect... 0 on ammonia, NO2 & NO3. New fish to be introduced either tonight or tomorrow to their new home.

 

[tropicfishman]

it might be, I've heard driftwood can do that, I noticed a huge difference in my two tanks. My 29 gallon has a variety of smaller fish and all real driftwood and some live plants, it stays around 7.0ish, but my 10 gallon with 2 plecos ( trying to get rid of ) and a big plastic center piece is 6.0, I guess the bio load always plays a role in PH

 

[Sidi]

The driftwood should probably lower pH, if anything, by releasing tannins (they're weak organic acids). It could have absorbed some alkaline compounds if it was soaking in alkaline water long term, I suppose.

Do you have any rocks in the tank? Calcium carbonate will raise the pH (limestone, marble, etc.). Also plants will raise the pH by removing carbon dioxide.

 

[spyyro]

I do have rocks in the tank. They are the smooth rounded rocks that are for ponds and things like that. They are mostly black and the one's that aren't are really dark in color... some with brown bands. I bought a bag of them at Lowe's around 3 weeks ago. They've been in the tank for about 2 1/2 weeks now. I boiled the driftwood 3 or 4 times, changing the water each time. I then let it soak for almost a week before I put it in the tank. I don't notice any tannins leaking out. I don't have any live plants in the tank ATM either. Is it bad that the pH is at 7.5? What can I do to lower it if that's what I need to do?

 

[jsoong]

7.5 isn't bad, as long as it is stable. You should find out what your tap water pH is .... then you would know if the pH is being lowered in the 29 (drift wood, lots of decaying stuff - mulm, etc), or rising in the 75 (most likely cause - rocks).

BTW, plants won't raise the pH by using up CO2. CO2 is constantly being replenished from air (assuming you have water circulating). Some plants can use HCO3 in the water & drop the KH, but that's a whole different story.

 

[spyyro]

I don't have any driftwood at all in the 29 gal tank. I don't have rocks in that one either. Everything that is in that tank is artificial with a gravel substrate. The new tank is a 75 gal and has one piece of driftwood, PFS substrate and artificial plants, for now. I'll check the level in my tap water tomorrow. We have a well here so that's a plus... no city water.

 

[Fishyfanatic]

As mentioned, it's not the driftwood. It doesn't raise pH values. Have you tested the rocks with the vinegar method?

 

[spyyro]

Actually, no I didn't. I thought if they were being sold as rocks for ponds and such, they would be just fine. Just put vinegar on it and see if it fizzes for the "vinegar method", correct?

I did manage to move 2 tetras, 2 rainbow sharks and my CAE over to the new 75 gal tank last night. I had them in a bucket w/ their 29 gal tank water and then gradually added new tank water over a period of about 30 - 40 mins to acclimate them. They are all fine this morning. I plan to move the others over today.

 

[Fishyfanatic]

I'd give it a try. It can't hurt. Just put vinegar on it and if it fizzes, there is your cause. If not, then maybe it's something else. No seashells or crushed coral anywhere in the tank?:

 

[spyyro]

No seashells or coral in the tank and the vinegar did nothing to the rocks but wet them. I tried 3 different ones. My other fish are being acclimated right now and I'll check params again over the next few days and see if there's any changes.