my first grow dont no y this is happaning

im haveing some problems wood like to no how i can prevent stuff like this. if u have any ideas pleas reply

From the look of those pictures your plants are in flowering.
During flowering most plants will have yellowing leaves, which start at some stage of flowering and continue until harvest.
Some growers can offset this by adding Nitrogen to their feeding schedules during flowering, but most people just let the leaves yellow and die off.

I would suggest pulling the leaves that are mostly or entirely yellow off the plant. And if your concerned about the other leaves yellowing too much or too quickly, add a little nitrogen to your feeding schedule for a watering or two.

the tips and sides of ur leaves r all crunchy cuz they r burned... thats y u got those dead shriveled up ones there too... yes remove ur yellow leaves by wiggling them and if they fall off then they r off... if not, try agn tomorow... yes ur leaves will go yellow in flowering, but in ur case, thats fert-burn damage in those pics... i would not sugest addin more nutes at this point as ur leaves r nice and green except the burned edges and the completely singed and dead ones.. next grow go ez on the nutes... less is more, cant hurt it... more is less, can kill it!!!

alright thanks guys um so the nutes i use r qwick bloow part 3, 0-4-4 qwick grow part 2, 2-2-2 and some ph down
but sense flowering ive cut dow on qwick gorw part 2 do to other posts i red saying that when flowering use vary
little nitrogen so i have been r u saying i shud cut back all nute or just nitrogen aswell ??

nutes period... how much longer u got left anyways?

well i just wanted to try this was a test i gess u cud say my lights r
just salt water fishtank lights so i still have a long time left wut i have thare
took like 6 monthes when i start next time im goanna b putting lots
money into it and i think im goanna try hydo but i think im like 6 weeks
into flowering

For the equipment that u r using, is why they are small, nute burn,flush with no nutes twice, looks like maybe even underwatering too.. I suggests using soil again, as it is much more forgiving than hydro... at least till you get a few runs in.. Good luck Peace

all right thanks i was goanna keep the mother soil and then start the trials and errors of cloneing

the main thing im concerned about is in pic 2 or is that minor