Mg deficiency? ? quick question

Hey everyone I think I have a mg deficiency just want a second opinion

Indoor
162 W of 6500k T5
Black Gold potting soil
Was using distilled bottled water now I'm using tap (260ppm) fed at a total 660ppm 3 days ago AN iguana juice grow
And rapid start at 2 ml per gallon about 3 weeks from seed

Silly question but got to ask it...

ur tap water isnt chemical treated is it? (Chlorine mostly)

It's city water so I would assume it is and no I didn't even let it sit out for a day... I will fix that next watering think that could be it?

660 is a little high for seedlings.but I suppose youre at 260 of unknown. at this stage i would give them flower ferts. they need P and K right now and hardly any N. this is why they are so bushy as well.

nute burn is what youre dealing with. minor. I would go fill the car with spring water gallons, or invest in a hydrologic 100 for around 160$

keep the PPms under 400 for fertilizer until they are at least 2 months old. seedlings barely need nutes in soil until flower

Cool thanks Elvis I'll tone down the nutes some and pick up some spring water and start looking into filters