There is a bit of a story here that I learnt from. Maybe others will too.
The tank is my oldest running tank (~12 years) and, arguably, the most stable:
50% Flourite / 50% pea gravel and river sand
4 x 65w CFL CoraLife: 2 x 65w 12 hrs/day and 2 x 65w 10 hrs/day on timers
EI at the low range
(currently) no co2
About 10? years ago:
About 4 months ago:
About 3 months ago I decided that good can be better and added a second Eheim 2026, both with spraybars, both clean, and both on full blast.
Better can be even better, so I also added pressurized co2 with in-line atomizer at the same time:
Set the co2 flow and double-checked everything over the next couple of days.
About a week later I got sick and could not take care of my tanks for about a month. The two largest tasks on this tank are 10-15g WC every 3 weeks or so and substrate vacuuming. The tank is relatively well planted with slow and fast growing plants. It does not house too many fish but it was home to 4 fully grown Red Parrots, 2 BNs, and a bunch of mutt corries.
Red Parrots are like our dog: eat well, poop even better.
In case we missed the lesson, here it is:
A lot of organic waste + high flow == gorgeous BBA in < 1 week
( with lots of plants and enough co2 to chock a horse)
A number of fellow TPT members have seen the tank in it's current state in person and, I am sure, they will vouch that that BBA is the darkest, thickest, longest, healthiest BBA ever. It actually looked weirdly beautiful on the needle leaf java fern. Took me a while before I decided that I should get rid of it.
If you look at the first picture in the OP, one thing might catch your eye: BBA all over the fern, outflows, intakes, etc etc BUT almost none on fast growing plants (like Green Temple) right next to it. The second lesson:
Your plants can out-grow the BBA.
Thank you for reading and enjoy: the BBA will not be in that tank for long