having issues in late flower, first grow!

[Biic]

hello community, i'm back again with even MORE issues to my Northern light auto grow. or so it seems, I noticed this morning some of the leaves have spots on them. This plant has had its fair share of illnesses but after giving it flower nutes a week ago i slowly started to see it progress as more flower becomes visible. due to lack of knowledge all the problems begin a couple weeks when i went heavy on trimming. The little girl turned into a short bush and i've been fighting to try and maintain it with LST since. I under watered it about 2 weeks ago and suffered even more consequences. Shes on day 58 right now, since this is my first grow ever i'm not sure if the spots on the leaves are due to illness or because the plant is going to be harvested soon. I have kept documentation of every single nute, feed and light schedule to try and find kinks easier along the way. could someone tell me when i should start flushing all the nutes out of it please? below i will leave pictures and a little more information about her. the last two pictures are my feed schedule i've been giving her. she was water'd and gave tiger bloom &big bloom.

Medium: FF Happy Frog
nutes: FF trio
3 gal fabric pots
light: QB288V2 RSPEC @ 175Watts
light is 18inches from top
light is on 20/4
temp has been steady at 77F with 50% RH
2x4x 5 feet tall grow box
the other northern light auto in the box is doing WAY better than what the bigger one looked at that age.
i feed once the fabric pot gets a little light/soil dries up a bit
never transplanted or used anything other than Grow big/big bloom & big bloom/tiger bloom.
PH'd EVERY feed/watering between 5.8-6.4
was using TAP water until a week ago, started using spring water.

 

[Garage_Grower]

Looks like the start of a calcium def, some of my plants do the same near the end of flower. I just bump up the cal-mag abit, and ride it out till harvest.

 

[Garage_Grower]

You may also want to keep your feed PH around 6.5, below 6 is too low for soil.

 

[Proph]

Hello. That looks to be an Mn (manganese) issue.. Most people that flush, start using water only about 7-10 days prior to harvest. Here is a chart I used slot while learning the deficiencies.. It will help you learn how to diagnose your plants yourself. It will take some time, but the learning is worth it.

 

[Proph]

Looks like the start of a calcium def, some of my plants do the same near the end of flower. I just bump up the cal-mag abit, and ride it out till harvest.

Keep in mind that calcium is a mobile nutrient ( see the chart I posted) and the issues start at the bottom of the plant (older leaves) and works it's way upward.. The spotting from a calcium issue is also rust/brown colored, not a redish/purple.. The pics posted of the issue all seem to be at the top of the plant or close to it.. He aslo stated that he was using tap water up until last week. Tap water has enough calcium in to satisfy the plants ca needs.

 

[Garage_Grower]

I always though Calcium was immobile, or at the least very poorly mobile. Good to know!

 

[LazyNhazy]

Looks like a ph lockout, by the charts your ph is going in too low. I would start using ph 7 water to slowly raise back up. And when you lose the mag Def you are good.

 

[Proph]

Looks like a ph lockout, by the charts your ph is going in too low. I would start using ph 7 water to slowly raise back up. And when you lose the mag Def you are good.

I was thinking lock out that is causing the Mn issue as well.. But nutrient lock out.. Not a ph lock out. The ph in soil is organically controlled by the root zone or rhizosphere.. So it will usually adjust itself as needed.. I was thinking more along the lines of a nutrient lock out because it looks like he added nutes every time he watered the plants.. I didn't see a line/day on his feeding chart that said "water only" or "plain water".. An excess of salt, or of one single nutrient, can cause around three other nutrients to no longer be available.. Excess in Iron can easily lock out Mn.. As can a ph over 6.0..

 

[Biic]

I was thinking lock out that is causing the Mn issue as well.. But nutrient lock out.. Not a ph lock out. The ph in soil is organically controlled by the root zone or rhizosphere.. So it will usually adjust itself as needed.. I was thinking more along the lines of a nutrient lock out because it looks like he added nutes every time he watered the plants.. I didn't see a line/day on his feeding chart that said "water only" or "plain water".. An excess of salt, or of one single nutrient, can cause around three other nutrients to no longer be available.. Excess in Iron can easily lock out Mn.. As can a ph over 6.0..

you're absolutely right, i never did water with just plain water without nutes. should i do that more often? & my tap water is high in cal so i'm pretty sure the spring water may have been the issue, started right when i used it for the 1st time. i do believe i locked the plant out by over feeding and this whole grow has been a mess. i appreciate everything you guys mentioned above. thanks for all the help, now the real question is what can i do to improve the other plants so i don't run into this issue with them?