aquaticscapes said:
Lighting in most is not strong, I would say more in the medium range, (consists of a total of 512 total watts over the length and width of the 125 gal., not great reflectors)
If that's T5 lighting then it's a lot of light.
Beyond a shadow of a doubt the appearance of BBA is a CO2 stability issue. It's an extraordinarily poor assumption that one has 30ppm CO2 in a tank. That almost never happens, especially with high biomass. GSA is both PO4 and CO2 related so this might confirm that you have poor CO2
for your given conditions..
CO2 grows plant mass and lighting accelerates the growth rate. I assume that since you're selling the plants you want to bring the crop to market as soon as possible. So there's no point in lowering the light intensity but there is every reason to improve your CO2. As Dan The Man mentions, 8 hours of light is about as much as you will need. The plants start to "close up shop" after that so leaving the lights on for longer only encourages algae.
There is no issue with pulling plants out of the bed as long as it's accompanied by a water change. It may not even be an issue without a water change as long as the substrate isn't disturbed too much. Good flow helps here too.
What's probably happening in a high biomass tank is that the CO2 levels fluctuate in the morning as the machines come up to speed. Removing biomass raises the CO2 level since fewer plants are consuming CO2. So if you're constantly removing plants with a marginal CO2 level the fluctuations give rise to BBA.
You need to change the injection rate and the timing so that the dropchecker is bright yellow at lights ON. Adhere to the 8 hour limit. Turn the gas off a few hours before lights OFF. This reduces CO2 consumption (which obviously affects your bottom line).
In any case, emergent growth is a much more cost effective way because you don't need to spend money on CO2, electricity for filtration and you don't have any algae issues to boot. Emergent growth also gives your customers plants with a higher energy reserve. It only makes sense to grow submerged specimens from species which have difficulty transitioning to submerged, not the easy varieties such as you've listed.
Cheers,