[I just wanted to start out in my reply that I've moved my stuff into the house as the garage is way too hot and I was worried my cultures would cook and rot.
They are in a closet so I don't have to see the light or hear the bubbling, which has been excellent. The heat in the closet with the door cracked open is about 80, according to my handy kitchen thermometer.
When I feed phtyo, I turn of the skimmer for an hour, and shake the 2-liter bottle thoroughly. I have a square glass that I bought at McDonalds a few years ago, and I believe it holds a good pint of fluid. I'll have to measure that specifically some time, but I fill it a little over half full and pour that into my 29g, and a full glass into my 55g. I do this every other day, but I'm tempted to do it daily.
I don't screen the fluid at all. All the bottles in my fridge are shaken every other day, because they settle and separate, but I don't know if that helps or not.
I divide up the cultures every Sunday. 1.5 bottles are used to make 3 new bottles, and 1.5 bottles are ready to use and are labeled and stored in the refrigerator.
I'm culturing brine shrimp again, to feed the goniopora and other corals. BrineShrimpDirect told me to keep a 100w bulb light over them for 48 hours straight, then harvest them for feeding.]