Oldman...I know the kh and gh of my other tanks being a 2 makes my water pretty soft but the ph in the other tanks is stable and very close to neutral. For some reason, this particular tank is just goofy. I didn't start doing large water changes until the parameters all crashed, before that it was only 15-20% weekly.
I have done countless hours of reading on diffent sites about ph and hardness since this problem started last week. The reason I started with several small shells is because I didn't want to spike the ph back up and shock my fish...and I was really trying to avoid "additives" or swapping out the substrate for crushed coral. I did try one other suggestion I read...baking soda. I understand that it, like all water additives, it a "temporary" fix. What I read said 1 tsp per 5g but again, wanting to go slow, I added 1 dissolved tsp to the whole tank instead. I tested the ph three time since then and it is holding steady.
On a happier note...I moves my first fry from the ladies tank to the boys tank today...three weeks old, a faint hint of color...but what made me really notice him was the "school boy on spring break" behavior...chasing the adult females, wiggly dances in front of anything that moved...lol. There may be a few more boys in the fry tank but I can't be sure yet. And given that it has been 22 days since this group of fry came along...I should have more very soon