I'll do my home tanks, and a couple of big ones at the shop. (there's around 250 tanks..
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)
Smallest is a 1' tank, so maybe 30 litres? No filter, light coloured 3mm gravel, plastic plant, a rock, some shells and a no fishing sign. I have Will Smith in there, he's my blackmoor goldfish. I did have an oranda and a ranchu, but they unfortunately had dropsy.
Next is 4 feet....So I'm going with 160 Litres. 3mm dark brown gravel, undergravel filter, external cannister filter. Both bio although Carbon is in external, water was too hard. Umm, Few terracotta pots, 150w heater. 4 10-12 inch oscars. 2 7-8 inch clown loaches.
6 foot tank. 220 Litres. 3mm course brown gravel. undergravel filter, 2 internal power filters, 300w heater. One fish, [i]vieja fenestratus[/i] few pots and plastic plants. He's happy,
6 foot tank again. 3mm brown gravel. hollow car, anchor, lots of moon rocks, lots of bog wood, lots of slate, lots of normal rocks, lots of plastic plants, a terracotta pot bit to hide in. 150w heater, 2 internal power filters, air tube stone, 2 air pumps for it.
Featherfin catfish, elephant nose, butterfly fish, 3 ocellatus, 1 angel fish, gold spot plecostomus, 2 bristlenose catfish, 5 clown loaches, 6 silver sharks, 6 venustus, 6 hongii,
30 L marine tank, 2 blue chromus, scooter blenny, crab, blood shrimp, 1 anenome, some live rock, 2 clown fish
270 L tank, underground filter. shovel nose catfish, eeltail catfish(tandannis), giant gourami(itola), sailfin pleco. Limestone and bogwood, 4mm course gravel.
270 L tank, UGF, giant gourami(clare), tyre track eel, 2 alligator gars(Horatio and hackeysack[he has a herniatus, looks like a hackey sack]), 3 or 4 catfish which I can't remember the name of, a bumblebee catfish
270L tank, mixed cichlids and catfish, all fully grown, maybe 30 - 40 fish. Hertweigi, brasiliensus, texas, convict, electric yellows, blues, blue dolphin, venustus, rostratus, parrots, peacocks, assorted catfish, silver sharks, black sharks, red tail sharks...Many many fish, don't remember what's in there.
then there's the 250 other tanks to look after which all have undergravel filters, power filters for tanks with dirtier fish, strips of non-toxic green plastic tied to rocks for aggressive fish. assorting from 60 L as the smallest to 300L as the biggest. Kept in an insulated shed. Not going to list all the fish we keep lol.
My favorites are probably Clare's tank and my 6 foot at home with the featherfin.