Lights on 24/7?

[Bamf Comics]

So I set up 3 plastic tubs, in the 10-12 gallon water capacity range. I hung 1 twin tube 48" fixture overtop. I was thinking, speed grow some cultures of live plants fast enough to be able to sell them in the store since the truck delivery wholesaler doesn't offer live plants.

I split an order of hornwort into all 3. One it's growing really well. The middle which should have the most light exposure is doing okay. The other end, barely there.

I also added guppy grass to all 3 and java moss which neither appears to be doing anything and may even be dead in the end tank. Java fern added to the first 2 as well. Who really knows what java fern is doing since it takes so long to do anything, live or die. I also dropped in a pot of dwarf lily into the first two tubs today.

I'm not happy with the growth so I'm switching the lights next week to a 4 tube set, (Hyper Tough 4-FT 10,000 Lumen Plug-In 4-Tube Integrated LED Shop Light Fixture). 100 watts.

Now I'm wondering
1- Stay with the 24 hour lights on schedule?
2- Any more plant suggestions for a bare bottom plastic tub? I've done anacharis before but if it's not standing up it gets all those white roots coming out every few inches if laying sideways. I may upgrade to some gravel later but I wanted simple for now and to let them double for raising livebearers and snails, maybe some shrimp later. I already got my first snails apparently that came in with one of the plant shipments multiplying like crazy. I'll add some fancy types later to snack on the sides once I make sure which one's will not eat the plants like apple snails. I was hoping the java moss might attach to the sides of the tub and eventually establish a permanent colony I could harvest sales qty from.

 

[Naughts]

I’ve not tried but I would not expect plants to do well with lights on day and night.

During the day aquatic plants photosynthesise, absorbing carbon dioxide and producing oxygen.
At night, aquatic plants consume oxygen and produce carbon dioxide.

If these natural patterns of respiration are thwarted, the plants biological functions (such as starch consumption) must become unbalanced?

 

[Bamf Comics]

That was one of the benefits originally to the 24/7 idea when I was wanting to toy with it as a sump. No worries about the plants outcompeting the fish for oxygen in the dark, no fluctuating ph from CO2 bouncing, continual removal of ammonia, etc as it's produced lowering nitrates, etc..... I set up 2 60 breeders and the plan was maybe to eventually do heavy store stock fish in the top tank and something 24/7ish plant in the bottom. I thought I'd read something on algae scrubbers and such years ago. I am rusty though so we start and trial and error our way with the tubs first. If you have some literature on this starch thing, the 100 watt light coming next week has me open to a 12 on 12 off alternative if there's some science or first hand experience behind it. I had a similar tank back in the 90's that I believe I was running 24/7 but it's been so long the memory plays tricks. I figured the biggest risk was nutrient depletion, but I've got quite a few over stocked tanks I can pull a pitcher or two of nitrate laden replacement water from as needed thanks to the oscars, angels and all those goldfish being pigs and always begging for more food. I figure as the tubs fill with fry, I would be feeding pretty heavy and frequently there as well. Wake up, put coffee on, sprinkle some powdered flake on the babies, at 6AM, 8 AM dip a pitcher of water out and replace while the bath tub fills up, feed again, 10 to 11 and somewhere around 2 feed again, feed again at supper time, feed again around 10 PM before final crashing for the night.