I have 11 tanks, as described in another recent thread:
I'm on DC (DCWASA) tap water, and also use Safe. I sometimes use rainwater as well and occasionally water from a dehumidifier, for corydoras, rams, nannacara, and pelvicachromis. All of my tanks have plants, but only relatively easy plants. Almost all my tanks have pool filter sand for substrate.
I use live food, too: mostly microworms, white worms, and grindal worms. I also can collect small earthworms from my compost bins.
Feeding varies. For most fish, I feed five days a week, taking Tuesday and Friday off. Based on the April meeting talk, however, I've been trying heavy feeding of corydoras on Saturday and Sunday, and then fasting them Monday through Wednesday.
For fry, I'll feed golden pearls and microworms. I often use the golden pearls in an Eheim autofeeder. I have two Marina breeder boxes, but have just begun using them, and put some corydoras eggs in one last weekend.
For adults, I feed a variety of flakes, pellets, and Repashy.
I change the water at least weekly, 50% or more, although I'm thinking about cutting back to see if that will affect spawning.
I have 11 tanks. Two are in our family room. One of those is a 20 gallon mixed community tank that houses the male offspring of the guppies and endlers my daughter wanted 6 or so years ago. (That's how I ended up with this addiction again.) Also has some neon tetras and 7 juvenile German rams. The other is a 10 gallon that currently houses only Celestial Pearl Danios and Rosy Dwarf Loaches.
In the basement, I have the other 9 tanks:
55 - mixed community. currently Bolivian rams and Laetacara Thayeri, some panda corydoras and a few other small groups of corydoras
10 - used for breeding whatever I want. Currently has some corydoras loxozonus. Has red cherry shrimp, as well. Last week it had six celestial pearl danios. Reminds me: I need to see if any CPD fry made it
40B - 2 pair nannacara aureocephalus, 7 or so gold laser corydoras (cw010), and 7 or so corydoras atropersonatus
40B - 5 Australoheros oblongum and 17 yellow cat corydoras (c123)
29 - Electric blue ram pair, cardinal tetras, and corydoras sterbai
29 - 3 serpae tetras, 3 black skirt tetras, a few female guppies, and lots of juvenile archocentrus multispinosa (free to members)
20H - pelvicachromis subocellatus and a group of corydoras melanotaenai
20L - corydoras erhardti and habrosus
15 - pelvicachromis roloffi kolente pair
All but one of my tanks have canister filters, mostly various Eheim models. I have one tank with an Aquaclear HOB and a couple ACs in boxes as backups in case something goes wrong.