Gold spots on the leaves

[marc2341]

Hi all, i am in need of help, my 2 plants of 5 weeks old have just started getting small gold coloured blemishes & i need to get on top of it.
The strain is blue cheese, under a 300w full spectrum led lamp, they are in soil bought from the hydro shop.
There has been no additives other than 1.6ml of mammoth P in 10L of rain water which is tested & adjusted to neutral ph

 

[GrimReffer]

Looks to be early signs of magnesium deficiency. You can use Epson salt for that. Also they look a little hungry, did the soil come with nutrients in it?

 

[ET12SECOND]

I would do a foliar feeding of some CALMAG plus. I would also add some none meal as it looks like they are light on Nitrogen. As mentioned depending on what you have in there to start with they look like they could use some food all around