i set this tank up a few months ago (new years day) out of stuff that was hanging around doing nothing. according to everything i have read it shouldn't work, but it is thriving, plants are growing and multiplying beyond belief thus far. had a short, 3 or 4 week algal bloom which disappeared as quickly as it came and now all is good.
the tank used to be home to my 30kg hand tame redtail catfish, who unfortunately died from a large cancerous tumour a couple years ago. it is around 1000 litres with the water level dropped a bit as it is (no lids). it had a very large, agressive, sump filter which i removed in favour of a small, underpowered, JBL canister filter in the hopes of leaving some nutrients in the water ROFL.. it is working like a champion so far.
i then plumbed in one of my D-cells of CO2 that i use for running air tools on site into a reactor made out of a gravel cleaner and some bio-balls. you can see the D-cell sitting on the desk in the first photo, it doesn;t fit anywhere else in the room ROFL..
then i hung a single 150w metal halide from the ceiling, this should be nowhere near enough lighting intensity, but is working beautifully.
went down the street and dug some laterite out of a ditch on the side of the road (cool huh?), threw some small river gravel that same from the local garden centre down over the top of it, ripped some driftwood and rocks from old tanks back out from the garden, threw some old tank water that i had saved back in there, rinsed off and planted some plants that were "in storage" in my pond, and called it good.
gave it a week to settle, then started putting fish in. couple discus cause they are cool, platies and gouramis because they eat algae and produce a lot of solid waste (can't be bothered dosing), some small things - zebra danios because they are fast, black neons, scissortail rasboras, hockey stick and serpae tetras because it seemed like a good idea. and ottocinclus and bristlenose cats because all the cool kids have them
haven't had a single fatality yet, and am now able to do some in house agriculture to perform additional aquascaping to fill in the thin areas with the plantlets and offspring from the thicker planted areas, so i am happy.