POND FISH GUIDE
Pearl Danio
Danio albolineatus
Small, active schooling danio commonly sold as Danio albolineatus. Suitable for indoor aquaria (17–27°C), omnivorous and beginner‑friendly. Not permitted in UK garden or wildlife ponds under current guidance.
At a glance
- Maximum length
- Up to 5 cm
- Temperature range
- 17–27°C
- Suitable for small ponds
- No
- Suitable for wildlife ponds
- No
About Pearl Danio
The Pearl danio (Danio albolineatus in hobby listings) is a small, active schooling fish widely kept in indoor aquaria. In UK hobby guidance it is treated as a typical small danio: hardy, undemanding of water chemistry, and a good choice for beginners provided husbandry is good. Important UK context: OATA and gov.uk guidance make clear that most ornamental freshwater fish (including danios) must be kept indoors under the Import of Live Fish Act rules. Pearl danios are not on the short list of species permitted for outdoor garden ponds, and releasing or allowing escape into wildlife ponds is illegal and ecologically risky. Do not keep Pearl danios in garden or wildlife ponds in the UK. Aquarium care basics: treat them as a shoaling species — OATA recommends groups of at least five, more if space allows. They prefer well‑oxygenated water and benefit from a moderate current/aeration. General danio guidance indicates a temperature range of about 17–27°C; species‑specific tolerances were not established in the UK sources consulted. Keep water chemistry stable: pH roughly 6.5–8.0, zero ammonia and nitrite, and nitrates kept low (OATA suggests around <~20 mg/L above tap levels). Filtration is mandatory; provide substrate, plants or ornament cover and a secure lid if required. Feeding and stocking: omnivorous — feed a good quality flake or pellet diet once daily (what they can eat in a few minutes) and supplement with small live/frozen foods such as daphnia or small bloodworm. Add fish slowly to an established, cycled aquarium. OATA gives general stocking guides: around 45 L as a minimum for a small shoal of small danios, and larger volumes (c.120 L) for bigger danio species; there are no UK pond‑volume/depth recommendations because outdoor keeping is not an accepted option. Pearl danios are generally peaceful but very active swimmers; avoid very timid or slow tankmates that will be stressed by constant activity.
Diet
Omnivore
Temperament
Active, schooling, generally peaceful; very active swimmers that can stress timid tankmates
Compatibility
Good with similarly active community species. Avoid very timid, slow-moving or long-finned fish that will be stressed by persistent fast swimming.
Care notes
Indoor aquarium only under UK guidance. Filtration and good oxygenation/moderate current recommended. pH 6.5–8.0, zero ammonia/nitrite, keep nitrates low (~<20 mg/L above tap). Cycle tank before adding fish. Keep in shoals (at least five); OATA suggests ~45 L minimum for a small shoal of small danios and ~120 L for larger danios. Feed quality flake/granules once daily and supplement with small live/frozen foods. Weekly water testing and ~25% weekly water changes advised. Add fish slowly as biological filtration establishes.