I wonder if it could be something else in the water preventing cycling? Would the lfs be in the same water supply?
You increase temperature to speed up the biological action of the bacteria. It makes them grow faster. This works up until about 100 degrees.While I may be wrong here, but I would keep it in the 77-78 range (at least that's what I do when cycling a sw tank) since that's the temp I plan on running the tank at. What's your water coming out of the tap at params wise?
The .5ppm ammonia is way better than the nitrates. A 50% water change will bring it to .25ppm where the BB in the tank quickly takes care of it. High nitrates in the tap are way more difficult to deal with.id rather have your 20 nitrates than my .5 ppm ammonia from my tap water. cycling was easy for me change 75 percent a day once i had nitrates i started adding fish had no trouble. its pretty bad if you feel safer drinking your aquarium water than your city tap water but i still use my tapwater for water changes i just do more frequent smaller changes than i would otherwise
Got a couple of pictures and even a short video of one of the little buggers...hopefully enough to tell what they are..
Video) http://vid43.photobucket.com/albums/e389/yracactuseater/164_zpse8d00d0f.mp4
The swimming action in the last pic looks more like some type of detritus worm. Planaria for not squirm like that unless you give them a shot of glut or excel.