Water params are am=0 ni=0 na=1to5 ca=400 alk=9.8dKh Io=.08 Ph=<.5 Sg=1.025 (refractometer) temp =77 to77.5 f pH=8.2 125 gal modified reefready w/2 maxi 400's, 1maxi 600 on wavetimer, 1 maxi 1200 on spraybar, rio 1700 pwered skimmer (don't know the brand, bought used) quietone 4000 return pump, 20 gal sump 2 diy coil denitrators (tested and adjusted) auto topoff , using ro water from glacier machine(tested for am,ni,na,pH etc.). We have blue xenia,pompom, anthellia,colt coral, frogspawn ,cataphyllia, rhodactis, zoanthids, poly's, montipora, alveopora,about 125 to 150 lbs lr, 4" to 5" dsb, 1 royal gramma, 1 lawnmower blenny, 2 neons, 1 sixline wrasse, 1 mandarin,1 yellowhead, 1 electric scallop, 1 green brittlestar, 40+ dwarf hermits (reds and blues), 20 nassarius,10 conch,20 or so astreas, 2 cleaner shrimp, 4 peppermint shrimp, 280 watts of no flourescent, and 470nm moonlights. Everything else is diong well. I think something got the annelid.