Is this a k deficiency?

[HarleyBlue13]

3 week of flower,
Leaves have progressively getting worse since about a week ago.
I have been feeding fox farm trio
Had an overwatering issue leading into this.

 

[GBAUTO]

Does appear to be.

 

[HarleyBlue13]

Does appear to be.

I recently started to filter my water, could this affect it?

 

[GBAUTO]

I'd say as long as you're following their recipe for the growth cycle, then the only other thing that I do is to allow my solution ph to range from 5.8 to 6.4 over the 10-14 days I run the solution. The variation in ph impacts how bio-available the elements are to the plant.