Burrows through the substrate, keeping the anaerobic layer from compacting. But with leftover food it multiplies explosively and can’t be removed.
The largest group where none died in 90 days. Tap water · black sand · bacteria starter on day 1 · fish added on day 10 · 25% weekly water changes.
Run a 60 cm standard tank with 68 yourself →The same rules the engine uses for tankmates.
No eating or bullying either way, with plenty of overlap in temperature and pH. Fish that swim at a different level come first.
The numbers on this page come from the Water Kiwoogi simulator model; real tanks can differ.