Please define the following parameters in Watts per gallon. Much of this would depend on nutrients and addition, and type of Co2 used, so feel free to throw in a qualifier.

1. Adequate

2. Good

3. Better

4. Best

5. Criminally Insane

I'll go 1st.

1. Adequate = 1.5 WPG < Suitable for low light plants, and non Co2 sytems

2. Good = 2 WPG < Suitable for low light plants, and easy growth speciecs with Low Co2

3. Better = 2.5 WPG < Suitable for most plants with good Co2, and Tanked Co2 is definitely a consideration ! EI Nurient dosing parameters really come into play.

4. Best = 3 WPG < with 20 to 30 ppm Tanked Co2 using EI nutrient dosing parameters. Consider a balance of both dissolved Co2, and Misting for optimum results. (Way too easy to maintain these parameters, and continued success is inevitable)

5. Criminally Insane = 4.5 to 6 WPG < Excess Lighting becomes an Impediment requiring constant tweaking of both Co2 and Nutrients often requiring unstable levels of Co2 in excess of 30 ppm. Nutrient potential exceeds the limits of Some plant species, and Especially Fishes, and Inverts. Losses in livestock may occur. Maintenance and monitoring of system becomes excessive, and personal Enjoyment flys right out the window !!!

There is such a thing as Too Much Light ! JMHO Your mileage may vary ? Prof M

I am becoming convinced that there are only two levels of lighting of interest:
Low - for low tech, no CO2, slow growing plants - about 1.5 to 2 watts per gallon.
Good - for high tech, pressurized CO2, for almost all plants - 2.0 to 2.5 watts per gallon.
All watts per gallon referring to quality PC bulbs in a AH Supply quality reflector, located 2 - 4 inches above the water surface.

Just my opinion, and that tends to change quite often.

Best 2 w gal
Better, 2-3w gal
Good 1.5 w/gal and 3-4 w/gal
Nuts: 5-8w/gal


Note, the above is using CO2 for all.

For non CO2: 1.5-2w best,
1-1.5w/gal better
Good: 2-2.5w/gal
nuts: 3w/gal

Regards,
Tom Barr

That's even less than I anticipated. The larger point being that too much light is actually detrimental. Perhaps not to the plants themselves, but certainly to the overall balance of the system, and balance and stability will produce optimum results in the long run.

I am actually accustomed to clinical systems, and even I find it tedious to maintain stable conditions over 3.5 to 4 WPG < I don't think tedious is what many of us had in mind for this hobby ? Again not a matter of "could it be done" but "Should it be done".

15 years ago my best results were acheived with 120 watts on a 40 long. 1 cool white, 1 warm white, and 1 royal blue. Still not sure how to feel about Blue bulbs, but Why on earth would I have expected plants to adapt to the industry ??? 15 years or not, the plants don't appear to be getting any smarter ? LOL. HAGLOM Prof M

I think another factor here is aquarist burn-out. Though I usually find pruning is relaxing, maintaining a high light stem tank can become so obsessive it can make the hobby a chore. I also find it's hard to progress with scape with such conditions, but in my case that's not just because of light

I find pruning, planting, water changes, and general chores quite relaxing, but given the peace and beauty achieved by those endeavors I find the chronic dinking with equipment, test kits, and light cycles an inane act of mental masturbation and an otherwise vulgar assault on sensibility, and reason !

But Hey...that's just me. LOL.

I think the best is 2-2.5 with CO2 and 1.5-2 without. Interesting that 2 wpg seems to be the sweet spot for any type of tank when using CF or T5 tubes with decent reflector and 10 hours (on average) photoperiod.

The rest ranges from questionable (3-4 with CO2) to insane (people asking what can be done with <0.5 wpg or trying to push into 5-6+). Even at 2 wpg I wish glossostigma would grow 2-3 times slower.

What I also find of great importance and relatively easy to tweak is a photoperiod duration. Lately I tend to start a new tank at 8 hours of light per day and gradually increasing it to 10 if I want more growth.

In my experience this way you can have a little more light but still have enough room for an error with CO2 and ferts.

Regards.

Vladimir.

Unfortunately trying to convince the general newbies and intermediate folks remains very difficult to achieve!!!


I wish more would listen.

I give them tonnes of examples of all the species that do exceptionally well, too well like Gloss etc even at low light, 1.5-2.25 w/gal.

Someone always says buy more light, or you need high light for Gloss, HC and most all the plants many think are cool.



It's perhaps one the biggest issues in the hobby today and has been for about 5-7 years now.


Regards,
Tom Barr

Of events. Take your pick ? Cause and Affect. Past poor growth was likely due more to a lack in Co2 and nutrients, possibly spectrum ? Once Co2 is applied, and nutrition is uninhibited...then acting on the blind presumption that light then becomes the limiting factor. Still when you look at the lighting systems availble right out of the box you begin to wonder why ??? If you don't have enough light you can always buy another light, but when you have too much light yer pretty much sub-marined from the git go ! Design, Industry, and Marketing may have changed, but they are still the same plants. Still it's easier to sell high output lights than to sell decent substrate, but which does more good ?