Hello as well, @BBradbury
As I said, I agree with you in principle about frequent and large water changes. I happen to think that this is a "best practice" as far as aquarium maintenance is concerned. Where we disagree is in applying this as a universal solution to all aquariums. I believe it works for you, otherwise you would not be advising it as often as I have seen on this forum.
Disagreement is good, it promotes discussion, I hope the civilized kind. Without disagreement, discoveries would not be made. New practices and new ways of doing things would not happen. Life as we know it would stagnate.
I define frequent WC as weekly or more frequent.
I define large WC as 50% or more.
Where a large frequent WC would not work as a universal solution-
In my personal experience, one of my tanks has a gravel substrate and five small fish. Low light, low light plants. I have soft water, TDS 20-25, so, minimal minerals there.
I did not start off with fertilizers, thinking the plants would be fine with fish food, fish poop, and water changes.
I had to change this practice. The plants started to show signs of deficiency, iron first, now potassium. Had I continued not fertilizing
and only doing WCs
, my plants would continue to suffer and algae would abound, even with low light totaling 7.5 hours per day.
So, I still do a 50% WC on this tank weekly, but I also supplement with a small dose of fertilizer. The tank is overall better with this regimen.
We are all different fish keepers with different situations. All I really want to say is that the hobbyist needs to tailor the tank tinkering to their own particular needs. One size does not fit all. Thank you for reading.
For my shrimp tanks I dose Excel and Fluorish comp weekly after WC, followed the next day by iron and Excel (mosses, low light plants in all tanks). So far it is working to keep plants healthy. Should things change, I would tailor my intervention based on the tank symptoms.