Trumpet Snails and PH
*if you don't want to read all of this, skip to the bolded section!
So, long story short, I set up a 2.5 gallon NPT (kind of) about two weeks ago for a new betta fish and so far, so good. The plants are growing, my fish is (seemingly) happy; everything's doing well EXCEPT the four trumpet snails I plucked my 5 gal and dropped in my new tank.
They don't have any physical signs of injury and my new betta has stopped picking on them since finding out they're not edible. These snails were doing fine in the 5 gal, but have become incredibly inactive now. Like, they will stay in the EXACT same place for three days straight. They don't move. At. all.
Two days ago, I decided to experiment. I took the snails out and put them in a little cup of water from my 5 gal. It took them one minute to get out of their shells and then they were back to crawling all over everything. I dropped them back in the 2.5 gal about an hour later and today they've barely moved despite me placing a piece of spinach in the tank for them to each.
With that, I figured there had to be something with the water chemistry in the 2.5 gal that wasn't sitting well with them, so I did some tests on both tanks.
The tanks themselves are similar in all respects. Both are planted with MCOPM; the 5 gal is capped with Floramax while the 2.5 gal is capped with petco sand. Both tanks are usually heated to around 80* (with the same aqueon 50 watt heater), plus or minus one degree. The 5gal is filtered, but the 2.5 gal isn't.
Neither tank has an ammonia or nitrite reading. The 5 gal has 5ppm nitrates, while the 2.5 gal has around the same (darker than 5ppm, but much lighter than 10ppm). The *only* difference between them is the pH. The 5gal has pH of around 7.6, but the 2.5 gal has a pH of 6.4.
I *do* have a small piece of driftwood in my 2.5 gal, and I think I read online somewhere that they can alter the pH? So if that's the case, what are my options? Thanks in advance!