i have an end to the drama, but now new questions arise
as i mentioned, I had removed the pirate ship....and left it out while I was at work. little pictus must have been buried in the gravel under his favorite locale, and after a few hours post removal of the ship, he surfaced...floated up through the gravel i suppose, because i found his very badly eaten corpus right where the ship had been. so that is the bad news. but at least i found him, i guess
but this makes me concerned. the very healthy pictus and swordtail, dead on the same day. in general, i have had little loss of life since i set up the tank. I lost no fish during the cycle, thanks to help from many of you...but since then, I had got 3 tiny albino cory cats (2 of the 3 acted lethargic for a few days about a week after i put them in...then 2 died), but the other has been fine for weeks since. also, when i got 2 sowrdtails, one died within a week, the other last 3 more weeks, died today
now...here is what i see...that little cory sitting in the bottom, not looking happy. of course my dead pictus catfish and swordtail, and now 1 big angel was sitting on the bottom. both big angels have white flaky on the fins, and the fins look rotted or chewed. for weeks now I have seen NO amm, no nitrite, and I keep the nitrates around 10. today when i tested, 0 amm, 0.25 nitrite (weird in a cycled tank...but mayeb from the dead dudes in for a day) and the nitrates were about 15. I just did a 20% water change. added prime and aqu salt.
should i treat the whole tank for ich

no one else but the angels have any fleck, and the angels only have it on the fins.