Is 1600 to 1800 ppm really necessary?

I'm growing ICE in bubble/DWC my ppm is between 1100 and 1200. I'v been reading that people go up to 1600 ppm or even 1800 ppm. My girls are looking beautiful and show no signs of lack of nutrients but I still find it interesting. Sorry, I guess I should just ask my question. Is 1400 to 1800 ppm really necessary?
Thanks for any input.

to me that seems really high... but you can always try it and see what happens, but id advise to only try it on one plant just in case. Some plants are hardy eaters

So is 1000 ppm to 1200 ppm about right?

1400 is fine if your plants big enuff.