Planted Tank Guru
Join Date: Dec 2012
Location: Hot Springs Ar. 71901
There are a few types of Flourish so Ill go/w the idea you are talking about Flourish Comprehensive. That is a nutrient suppliment. it does NOT contain all of the nutrients that plants need. Potassium is the nutrient which has holes in the leaves as a symptom.
What could be happening is that the plant growth accelerates when you add some nutrients, but doesn't have enough of the Potassium it needs so it's scavenging some
from it's older leaves. Usually, a plant will not grow if a nutrient is left out completely.
If you want to test this try adding Potassium at the same time as the Flourish.
1/16 tsp is good for a 10g and just multiply it from there for a larger tank.
Potassium is in either KNO3 or K2SO4. That is 1/16 tsp dry fert. Use the directions on a liquid.
If you are talking about Excel, yes some plants are sensitive to it, Vals being the number one on that list.
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