Lowering Nutes

[Unexpected]

Do I need to keep my working ratio of nutrients if I just want to lower one component of my mix? I want to lower NO3, but should I adjust everything to keep my current ratio of NO3 to PO4 to K?

 

[BigWave]

Your overthinking it buddy. Toss them ratios out the window and dont think about them any more PERIOD. Any and every tank is totally different when it comes to consuming nutrients. The plants we use, the plant mass, inert vs nutrient rich substrate, heck the type of rock you have eg raises kH or gH or both. So many factors go into how the system works.
I know some dosing regiems like PPS-Pro or The Redfield Ratio dosing of 15/1 N to P etc rely on ratios but this is old school thinking and we have come far since then. Think of it this way when dosing Full Ei we do this so that the plants have everything they need and then some. They take what they need out of the water coloum then we flush the system with a water change and start over.
To get technical this is why the major fertilizer company's all have each salt in seperate bottles. This way you learn what your tank needs and dose each element individually. For most of the All in One fertilizers they are all based off of the old Tropica Plant Nutrition fertz give or take some numbers.

 

[BigWave]

Another way some people do what your asking is simply remove the NO3 out of the equation and replace it with say NH2-N from Urea or NH4-N from Ammonium Nitrate. For those suffering from the eternal Green Dust Algae this is a trick to eradicate it and not have it come back.

 

[Unexpected]

Copy that and thank you! Yeah, I had a momentary over thinking moment. I won’t let this happen again

 

[GreggZ]

Agree with what @BigWave said. I wouldn't worry too much about it. Contrary to what some say I have never seen any magic ratios. There are dozens of things that are more important.

That being said if one nutrient is WAY off from the others that can cause issues and a deficiency. But at the levels most dose at that is not much of an issue.

And in the end, there is only one way to find out. Try it in YOUR tank and observe. Tried and true method of dialing in ferts.