Potassium toxicity in hydro

My bud growth has slowed and I believe excess potassium is to blame. Top leaves are yellowing a bit and getting spotty.

Assuming it is an excess of potassium, can I fix the problem just by adding fresh water to the reservoir and bring the concentration down or do I need to do a complete res change?

Here's a one week comparison going from weeks 5-6. The top one is week 5.

Personally I see a fair bit of bulk difference in the 2 pictures

I wouldn't panic, but when I did hydro if I suspected a nute problem, I would flush and change the rez.

The8thChevron said:

My bud growth has slowed and I believe excess potassium is to blame. Top leaves are yellowing a bit and getting spotty.

Assuming it is an excess of potassium, can I fix the problem just by adding fresh water to the reservoir and bring the concentration down or do I need to do a complete res change?

Here's a one week comparison going from weeks 5-6. The top one is week 5.

View attachment 4839223

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Do you do weekly reservoir changes? Cheers!

Wastei said:

Do you do weekly reservoir changes? Cheers!

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I do

The8thChevron said:

I do

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That's good. I would personally try to lower the strength of the feed. Only time I get deficiencies in DWC is when I'm lazy with the res changes.

All my girls need lower feeding strength in late flower though. Maybe yours is trying to tell you the same thing? Hope everything's get sorted out bud! Cheers!

Wastei said:

That's good. I would personally try to lower the strength of the feed. Only time I get deficiencies in DWC is when I'm lazy with the res changes.

All my girls need lower feeding strength in late flower though. Maybe yours is trying to tell you the same thing? Hope everything's get sorted out bud! Cheers!

Click to expand...

I had the feed down perfectly, but I added a second light. Temperatures increased and so they drank more water and needed less nutes as a result. Still trying to figure out their new balance.

I've had similar issues when I don't wanna do a full res change but in this case I had done a full change only a few days prior. I knew I could dilute the res to bring down the ec but I wasn't sure if this would give me issues like when I wait too long for the res change.