hyphessobrycon erythrostigma

After 2 years without a tank, I recently started with a new one. A Juwel RIO 180 (180 liter/47,5gallon), set up with some plants, leaves, stones, wood and sand. Couple Herotilapia Multispinosa (Rainbow Cichlid) and 12x Hyphessobrycon Erythrostigma (Bleeding Heart Tetra). I replaced the...