a 1000 light i would imagine that if your plants finish bout 2 feet from the light you will be fine.. my 600s finish about a foot away bare bulb
my pump is like 500+ gph, depending on the medium i feed anywhere from 4-8 times a day..
a screen will help hold em up, but unless you did a scrog type screen it wont make a huge difference..
no it does not cover a foot and a half.. as you can see i have 2 600w bulbs that cover about 6 feet vertical.. it is a tad more intense in the middle but there is not a huge difference. he probably has never grown vertically and is telling you what the reflector dealers tell him LOL
send me a link to your journal and ill see what i can do
and round 3 has started, i am waiting till i start flowering to show off my new goodies haha