My male's in a drum-shaped clear glass salad bowl, almost 10in. across and almost 5 in. high, filled almost to the brim, with a clear glass dinner plate for a lid. He comes around to challenge any movement near his bowl, which is stuffed with small bits of dwarf Anubias Barteri, young plantlets of the delicate form of Java Fern, shreds of Java Moss, and even some duckweed. He snakes around everywhere through his weedy swamp, and flares at the female in the square water jug next to him. She has a shred of Bolbitis fern attached to a bit of pumice rock, more Java Moss and a young Java Fern in her place,
There are hardly enough gravel grains mixed with some crushed coral (my water's very soft) barely to cover the bottom. No heater *temps drop to the low 60s at night). No filter.No light (daylight from a window three feet away) No ammonia (the plants suck it up). No nitrate to speak of (plants get the N instead of nitrifying bacteria). A few Red-rimmed Melania snails.
I change 50% of the water every ten days or so. It's always crystal clear. Very little algae at this time of year.