Should I be worried?

Also, just wanted to add that watering with just water is never a good idea in coco. Feed-water-feed schedules are not beneficial and neither is flushing with just water.

if you need to flush, just do a flush.. the point is to reduce elemental ppm, so adding stuff is conflicting with that. don't flush in bloom if oyu have no reason. only hurts yield. it's useful if there's a toxicity, but i don't think ther eis. i think leaves look fine on second look.. i got focused on question alone, if you read previous answer, lol... You provide tons of Ca, and likel yMg too, so only add more in reaction or more likely ease back a bit if you encounter a problem.. that's a great time to irrigate water-only for a second or two. With 50% runoff you likely can't get a build up. save some money and do 20% when you irrigate or fertilize.

I'm thinking they look fine and healthy! why change what's working? Keep it up man Beautiful plant!