It’s new, I didn’t check ec but lowered my nutrients a little over a week ago
Plant still has a good couple weeks left, if not little longer.
Might have cut nutrients a bit short.
What should the ec be around during the last week or two of flower?
Never really dips below about 1.8 - 2.0 EC for me. From veg to flower.
Though truthfully, the last several days to a week, I just give them water.
That's out of pure lazyness and plants are so close by then, it doesn't matter anyway.
But that's me, others feed less, some more.
I wouldn't ever take it over 2.0 EC to be safe.
Yes always runoff but I only feed once every other day in 5 gal pots
In future you might find it better, to feed once daily, as a minimum.
Add some perlite if you think it needs more aeration or drainage in larger pots.
Though straight coco's generally alright on it's own.
should I do a run off test to see where is at?
Only if it's to rule out high EC in the media. Best it ever is, is an indication too. Otherwise unreliable.
I would just take it easy. Keep feeding nutrient to runoff. Ride it out, chalk it up for next-time.
About 1.2 EC would be my minimum input, personally.
With good drainage and aeration, which coco has, you should be able to follow manufacturer's feeding chart, for inert media, or DTW garden.
It's when coco starts to dry often, that becomes a problem, coco's a big sponge.
Performs better with once daily, to multiple irrigations per day.