It has been pretty well documented that a split photoperiod does little to nothing in terms of fighting algae or promoting plant growth. Your best bet is to figured out how long you want your lights to run and adjust fertilizers and CO2 levels accordingly.
Wow! whoa there horsie! hahaha! my favorite TB statement was this one:
"Never a one trick pony". I've noticed not everyone tanks with an adjustable CO2 system.
I'm unconcerned with the technique as a means to control algae growth. So plant growth is the primary goal. With a low-tech tank I'm not expecting a high growth rate, but just fuller, greener, lusher, healthier plants in general. Since aquatic plants are limited by CO2, Walstad's measurements with a siesta regimen, which show that CO2 levels rebound with a 4-hour siesta) are a good argument for trying this technique.
But you're right, a higher CO2 level in the tank does not necessarily mean that the plants are going to grow better/stronger/faster/healthier. I'd be interested in seeing the documentation you're talking about that shows that the siesta regimen doesn't promote plant growth.
Well worded reply
My documentation is "Tom Barr said so" - Don't have a link, but it was either here or on his website.
It's always best to remember,,, never say never,,,, never say always.
Those that are devoted to the MTS enriched soil method state organic content is to be avoided and causes problems. NPT depends on the soil organics as part of that method, polar oposites of opinion with the same goal.
Different tanking conditions would modify the results and or possible benefits. Having a lot of surface disturbance or running air pumps to drive air stones the CO2 rebound would be nullified. Comparing NPT to injected CO2 methods is mixing into a debate like which is better,, apples or oranges? It's a personal choice of method not a race.
I run split photo periods on a number of tanking systems and have for about 3 years. The average is about 8-10 hrs. between photoperiods. Whether my fish think they are twice as old as they are in reality because they 'see the sun' twice a day I don't know
. But things appear good.
Plants growing, shrimp and fish spawning and producing young. As long as the system has a rest period and consistent schedule I think all parties adapt to the environment.
(note) I did start splitting the photoperiod on low light tanks to help with thread algae and think it helped along with other adjustments. Ignoring the rest of the thread topics LOL