The "evil twins" were 1" and 3/4", the Tang is 2 1/2". Either way they are no longer an issue, as they have been taken back to my LFS.
Water was perfect: Amonia/Nitrates/Nitrites= 0's, PH= 8.2, Kh= 12 drops. I've been adding "Kent" Calcium something or other for a week (2times a week) and have been using something to raise the water hardness (clear tub about 20oz w/ a white top and purple label, don't remember the name) for 2 weeks.
The 301 Power Heads are both submereged comletely, the 402 has an open air line and is running the Protein Skimmer. I have a BioWheel 170 that is rippling the water surface.
I had Ammo Chips and Carbon in the 301's (taken out today) and replaced the sponges. Also had the carbon sponge thing in the BioWheel (also taken out today).
I had my LFS test a "pre-water-change" sample as well as a "post-water-change" sample and both were perfect, the 'post' needed one more drop to get the Kh right (12post vs 11pre).
I'm at a total loss right now, the Blenny looks happy and the new Juv Naso looks very happy, although he like to play hide and seek. Everyone got a dinner of live brine tonight, I'll update in the AM.