pH issue

Question
QUESTION: It's me again. Same tank as before, 10 gal, 4 sunset fire platys, 1 black mollie. Tank temp is 80F still, Ammonia 0, nitrates/nitrites 0. Tank has live plants, Pleco hasn't been put back, I got 2 otocluncus catfish to replace him with, but they are in a separate tank as i just got them.

My problem is keeping my pH where I need it, it keeps dropping down to around 6.4, when I need it to be around 7+  for the platys and mollie. I've been using API's pH up drops once a day for the past 4 days, and its not adjusted my pH at all. What can I do to help raise it?

Also, I'm planning on putting in a piece of driftwood i bought at the LFS, its currently sitting in a bucket soaking to make sure all the tanin is out, would putting that in affect my pH at all?

ANSWER: Hi Joseph:  A couple of things... Stop using the pH chemicals they are not stable and you will have to keep buying them and adding them and the fish will eventually suffer.  You can raise the pH with coral gravel  put in 1/4 of a pound at a time and test the pH after 24 hours.  I love driftwood...but it will lower your pH... so make sure that when you use it that you monitor the pH and add coral gravel to adjust for the driftwood.  Add the coral gravel in small doses 1/4 of a pound at at time because you do not want to stress out the fish.... keep me posted... dave

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QUESTION: Ok I'll look around for coral gravel.  Should I replace some of my gravel already in the tank at a 1:1 ratio or just leave it in?

Answer
I would leave your gravel in the tank and just add in the coral gravel. You can place it a media sock to keep it contained. If you place it in a media sock you should place the sock in the area of the tank where the filter water is most active... such as under the down spout.  dave