Nutes for seedlings or no?

This is my first grow so I want to make sure I'm doing everything correctly.
Here's a little background on my grow:
6 plants, 1 week old now (Snow White from Nirvana)
400W MH lighting
DWC setup (rockwool and hydroton medium)
4 reservoirs (1 reservoir has 3 plants in it, the other 3 have just 1 plant)
I use tap water with an out of the tap PPM of ~50

My little guys are about 1" tall now.
I've been reading up quite a bit on the subject of whether or not to add nutrients to my water for my seedlings.
Most people on the board seem to agree that, no, it's not a good idea.
Most of the FAQs and the distributor of my nutrients (Advanced Nutrients), say yes, the PPM for seedlings should be 200-300.
If most people's solution is to not use nutrients this early on ...why? What's the harm at that low a level?
I'm just a new grower looking for as much information as possible.
I appreciate any information you guys or girls can offer. Thanks!

Id say depends on what u want..If u want ur plants to grow as fast as possible which im sure u do then follow the reccomended dosing of ur nutes...General rule of thumb i follow is I begin feeding when the roots hit the water..But my ppm is already 400..
Id definetely bump them to at least 300 and see how they like it..Dont want to hurt them but if they react with growth explosion then u know ur doing everything right..
I have found tho that Ur plants will usually outgrow ur veg station with the reccomended dosages in latter grow phases..mine rarely exceed 800 by then they go in flower at a foot usually within 3 weeks.I have a small veg spot tho..
That 400 is gonna grow some monster's fast be carefull haha.
Good luck man.

You need to add Cal-Mag or equivalent if you have low ppm water. A lot of tap water already has micronutrients in it.

Thanks for the advice! I was thinking about starting at 200ppm and see how my guys respond.
I will definitely try out the cal-mag.

Your gonna jinx it calling them guys and get all males.

Luckily I'm not too superstitious ...although you have got me a little worried!
Hopefully my girls will be fine

you will probably notice your seedlings turn a light yellow if you dont give them any nutrients, because they are in water and can only grow on their stored energy which is limited because stored energy is only to get them through the soil however if they were in soil they would be just fine without any nutes for the first few weeks!! i learned this the hard way with my nirvana white rhino.. just remember to wait atleast 4 or 5 days to see what happens befor increasing ppm.. in the case of seedlings less is more!