That, partially, was my point: co2 in itself is not a fix-all. There are more interrelated factors at play and every new configuration teaches me something new.
Imho, the often-heard comment "oh, you need co2 with that light" gives people the false impression that the only thing they need to make their tank "blossom" is to spend yet another $200-$500.
Instead of that parrot comment, why not explain how and why? Why not give examples that show people that this hobby does not have to be expensive? You can throw $$ at a problem and get more problems in return. Why not explain the basics before upping up the ante? But I end up talking to myself.
That tank is in the master bathroom, a study in contradictions. A cheap Petco's special, with (first) cheap junky measly light, and an even junkier $60 "375 gph" canister filter BUT with multi-type AS and $250 self-build co2 rig with Cerge's reactor. Not a single fish > $3. Yeah, I have done that before and I knew how to do it "right".
Yeah... Right...
A gorgeous tank the first 2 months. BBA, GSA, thread algae, you name it, everywhere for the next 6+. Gassed fish, dead plants.
The co2 is gone. AS replaced with innert sand. $200 Eheim and $500+ light, both of which I can control. Another contradiction. Stop by, have a look.
Oh, the low light, no co2 75g is still producing A+++ grade BBA. The 65g with PAR of 120 @ substrate and with co2 up the gills and 2 x Eheim 2075 is still a plant farm. Any plant. The 12g is full of Rotala macrandra again. And no filter, no heater, no ferts, no nothing < 2g 'tanks' get no cleaning or WC. Did I cover the permutations? TVM.
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