Yes, they can severely lower pH. I'm no expert, but my oak leaves (which treat the same way as IAL) lowered my pH from 8.o to 7.5. The fish certainly liked that!
I see you have Mysteries. Are they in the same tank as your Betta? I have both in one tank, but I'm not sure they have same water requirements. Am I over thinking the Bettas and Mysteries water needs or do they have problems in the same tank?
Wen I had heavy tannins with lots of Indian almond leaf, driftwood, and Indian almond bark my mystery snails did fine and actually thrived and so did my bettas. Actually in the wild the Bettas water is stained brown with such heavy tannins from tons of Indian almond leaf, bark and driftwood. They love being in a low PH environment.
Yeah, when they start to need calcium supplements but they can withstand a lot of things.. But they do their best with a high PH and hard water but the tannins soften the water, they do equally as fine in softer water as log as it doesn't go below 6.5 ideally, because there she'll starts to soften, the IAL should make it that bad because as I've said I've had them in soft water like my planted tanks and fry tanks
Iv'e never really understood PH, GH, KH and their affect. I have Mysteries, Nerites, a Betta and soon will have a couple Rabbit snails. The Nerites have nice shells but the Mysteries have dingy, dull rough looking shells. I added cuttlefish bone to help the Mysteries' shells, but it hasn't made a difference.
What I should have asked is will my Betta and snails be healthy in my water?
PH-7.8, GH-7, KH-4 Is there anything I can do for the Mystery shells and how will it affect the Betta? How would IAL or oak leaves affect the snails?
LBF and the "wild" keepers advise me that IAL does lower pH, but not that much. And I'm sure it depends on KH (carbonate hardness--magnesium and calcium). KH buffers the water preventing pH from drifting, especially lowering. Knowing that Oak leaves really lowers pH is very useful. Thanks, Elsewhere.
In "soft" water, without much buffering (low KH), the pH can easily drift up and down. Going down too far into the acid range (<7.0 pH) is bad for snails and some fish. Betta, in general, like it <7.0 pH. Many, especially wilds, like <6.5pH. It takes pretty soft water to achieve that.
Low KH (buffering) can be dangerous, as when a sudden (unbuffered) rise in pH allows ammonium to convert to free ammonia at higher pH. This can cause deadly ammonia shock.
I'd sure like to hear what Rickey has to say about the relationship between KH and pH.