Anyone else have any theories as to why my Ph keeps dropping. I know most people have the opposite problem (maybe I should get a SWG )

I have been seeing my Ph drop 0.3 every couple of days. And though rain does seem to play a factor, this seems to happen even when it hasn't rained in quite a long time.

I still plan on raising up my TA a little more, to say 110 or so to see if that will help but just keep forgetting to get some Baking Soda from the store.

Thanks,

Riles