Maturity for SPS corals

[Viccy]

Hi, I´ve had my aquarium setup for about 3 months now and I have 50/50 soft corals and LPS in my tank. I also have a BTA thats doing great and growing fast. With that said, all my values are correct from my understanding to keep SPS corals but when I asked my LFS they said that I should wait a year before I started keeping SPS. What is it exactly thats going to happen over time that I can´t fix myself?

My values are:

Ammonium = 0
Alkalinity = 12
Nitrite = 0
Nitrate = < 1
PH = 8.0
Calcium = 480
Magnesium = 1480
Iodine = 0,06
Iron = 0 (This should be closer to 0.15 so this is in progress.)
26°C degrees

Thanks for any replies!

 

[CommsTech]

It is good to add sps to a mature tank but I don't think you have to wait a year. Most people add them after a few months. Although I would slowly lower your ALK as I think 12 is too high for SPS. I keep mine between 7 and 7.5

 

[Stackemdeep]

This explanation made a bit of sense to me when I researched the same question. Good Luck.

http://www.reefcentral.com/forums/showpost.php?p=21375899&postcount=7