Red plants and fertilization!


Junior Poster
Nov 26, 2007
Mogi das Cruzes - SP
Hi, in a talk with a friend, my friend said that with strong fertilization he had his red plants less reder than in non fertilized tanks, are there any relations in the "red factor" and less fertilization, I used to think that the color of the plants came due to regular fertilization and of course optimal uptake of iron form this plants, am I wrong?!?
My friend is using only KNO3 as a fertilizer on his tank...
In my new tank I'm using the solution I asked before in a topic (rexolin cxk - basically K2O and micronutrients) and I don't have my red plants as I would have them, one important fact that I would not have to pass is that those ammannia senegalensis that I sayed came from my emersed bank and now started to become red.
Before that adaptation from emersed to imersed form I had so much rugged leaves as it comes to be in a lack of potassium even adding potassium to the water column but now it's a solved problem adding just K2O...
Thanks in advance!

Greg Watson

Staff member
Jan 23, 2005
United States

There is always a controversial debate about "reds" ...

So let me comment quickly here - what your friend told you is very commonly reported. Thus you will often hear people argue that to keep "reds" you need to maintain nitrates at a significantly lower level ...

So if you want a "simple" answer - then what your friend told you is commonly true.

However it is true only in the context of the "effect" - but not necessarily the cause.

It is also not universally true from one plant species to another ...

As you have demonstrated yourself - you have ammannia senegalensis growing well with developing reds in the coloration ... and I suspect that is with a strong fertilization routine.

There are so many variables in tank environmental conditions, water quality, water characteristics, light, and fertilization - that if you are having success, keep up what you are doing.

There are quite a few threads here in the Barr Report on keep reds ... but you need to read them closely to take into consideration other factors in the tank.

I think you will find that the general recommendation is to create an environment that limits NO3 ...

However, for many plant species, I attribute the "effect" more to the slowing of the growth rate. I can usually turn new growth bright green for any red plant by simply cranking up the light and CO2 to stimulate rapid growth.

In my personal opinion, this is why so many of the traditional "stem" plants that grow more rapidly are harder for most people to maintain in a brilliant red quality and still keep them healthy...

I prefer to study what the water quality conditions the particular species prefers ... then maintain that water quality (some species prefer software water) and a light level that maintains slow to moderate growth ... I've never *not* been able to keep red plants using this approach. Now that isn't always optimal for other plants in the tank, so there are always tradeoffs ...