HI,
250 is high but I agree dropping it too quick may cause more problems.
I do thing the nitrate levels race is abit too much, all tanks are closed systems and so to expect and chase the below 1ppm is something alot of us cant get too. Or have the time or money too.
If the fish are acting fine and feeding then dont worry to much.
It's different if you have a few $1000 of coral in tank, but spending your time checking levels every day it just crazy. If you have had your tank for over 6months you can spend 5 mins in morning and you can tell if all is ok.
But for people who like to spend their time doing chemistry tests I guess it's fine for them but I keep fish to enjoy not saltwater to test.
IMO this testing has just gone too far and is a money making game or a hobby to brag to your friends. Mines smaller than yours. HEAT will kill your fish alot quicker than No3
Ande