What's This?

Hey guys this is my friends first grow. Would much appreciate some info and help.

Strain: Autoultimate & Jack 47
Grow: RDWC
Lights: 300W LED, 2 x 125 CFL
Temps: Day Min 20C Max 26C
Night Min 18C Max 23C
Humidity: 50%
Water temp: 20-23C
PH: 5.8
PPM: 700-800
Light Time: 12/12
Nutrients: House and Garden Lineup

The autoultimate is only a few weeks away from harvest and the leaves have been turning brown at the tip and curling upwards for about a week or 2 now and the leaves are starting to get spotty.

The jack 47 has been extremely slow growing the past week or 2 and has recently just started to brown at the tip and curl up.
The jack has been trimmed a couple days ago and cuttings were taken almost a month ago.

Would much appreciate any help! Thanks.

im pretty sure you have spider mites, and thats more of a problem then the tips browning.

Very specty, specs seem more of an infestation, anything nute wise is more of a more complete fading or burning of leaves

Do you have any type magnification tools available? Check the undersides of the leaves for anything, or inspect for small webs by misting lightly under leaves etc...

Roots are kinda brownish, but i'm assuming by color of water it maybe stained from nutes. Definitely check out for some kind of infestation

I will go get a magnify glass today to see if i can find any form of infestation.
Thanks for the advice guys

Can't find any form of infestation but there are definitely a few leaves that look like they have been attacked by something