Leaf tips turning brown and yellowing!

Could anyone here take a look at these pics and tell me what might be wrong with my girls. Leaf tips turning brown and yellowing.

spider mites I would say look to be the major problem, look under the leaves for little black spots and clear/white eggs

you totally are giving them to much nutes... but thats just one of your problems..
you better stop feeding them and get them mites under control b4 its to late...
remove the leaves that have 50% or more damaged by the spider mites then spray with organocide or any other mite killer...then after they are on the run you can start to feed again but in a mild dose, and alternate your feedings with plain water...

pic 2 looks like spider mites, also your pics 3,4,7, look like nutes, iron or phosphorus. get some florotmite, and spray your plants, those mites are very quick to destroy. then you may want to start buying a few different mite killers , cause they usually get used to the chemicals and if you keep changing them up, they will go away. never spray them during flower, always in veg...with the nutes, i would flush them next time you feed cut the dose in half, some nutes are notorious for nutrient lock out cause there so dam good. if you get the floromite (on ebay) you can buy it for 25 bucks, it last for about 3 weeks, wich is what you will need to get rid of those frickin mites, ive had them a couple times but you get used to fighting them and not panicking after awhile. these are the same pests that kill roses and other plants right outside your door. so dont get flustered, be patient take your time but spray them quickly, if all you have is cold water it helps! good luck.

thank everyone for input im aware of the little 2 spotted varmits using azamax they just got their 3rd treatment also just got some sns217 its supposed to kill the eggs to but cant use that it in bloom will try it on veg. using fox farms ocean forest soil and neuts. pic 4 i screwed up on mix too much big bloom only did 2 plants before i realized my mistake. so i flushed all bloom. first water after was just cal mag and super thrive next water was 1/2 strength neuts they have only had 1 full strength neuts sine start of bloom trying not to over do it . watering every 3 to 4 days . neuts every other water. will try sticking to 1/2 strength from here on. going to set off a fogger next week dr doom.see if that dont help kill the little bastards. there in bloom and veg rooms what a battle

Over feeding.

Spider mites look like this. Compare it to yours to see if that is one of your problems.
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