Van Heurn’s Rainbow
Van Heurn’s Rainbow (Melanotaenia vanheurni) is an attractive and uncommonly available rainbowfish from the Bird's Head Peninsula of West Papua. Males develop a warm golden-orange body with iridescent highlights and the characteristic dorsal ridge flash that rainbowfish are famous for. Named for Dutch naturalist and collector W.C. van Heurn.
Feeding & Care Tip: Sera Vipan Tropical Flakes and Hikari Micro Pellets make excellent daily staples. Supplement 2–3× per week with Hikari Frozen or Freeze-Dried Bloodworms. Crush flakes for juveniles; soak pellets.
Native to the Bird's Head Peninsula of West Papua, Indonesia. Inhabits slow to moderate flowing streams and river margins. Care requirements follow standard rainbowfish guidelines — slightly hard, neutral to slightly alkaline water with good filtration.
Keep in groups of at least six with mixed sexes. Completely peaceful with other medium to large community fish. Its relative rarity in the hobby adds collector interest beyond its attractive coloration.
A well-planted aquarium with open swimming space in the center replicates the rainbowfish's natural riverine habitat. These are active, fast-swimming fish that appreciate length more than height — a longer tank allows them to build up speed and display properly. Good filtration and regular partial water changes are important, as rainbowfish are sensitive to deteriorating water quality. Avoid very small or slow-moving tankmates that may be outcompeted at feeding time.
Care & Ideal Parameters
| Difficulty | Easy |
| Temperament | Peaceful — Community |
| Typical Adult Size | 4.0 inches (10 cm) |
| Min. Group Size | 6 minimum — mixed sexes for best male display |
| Ideal Temp | 72–82°F (22–28°C) |
| Ideal pH | 7.0–8.0 |
| Ideal GH | 8–20 dGH |
| Ideal KH | 4–10 dKH |
| Staple Food | Sera Vipan Tropical Flakes; Hikari Micro Pellets |
| Treat / Supplement | Hikari Frozen or Freeze-Dried Bloodworms |
| Origin | Bird's Head Peninsula, West Papua, Indonesia |
| Notes | Named for Dutch naturalist W.C. van Heurn. Uncommonly available. Warm golden-orange male coloration. Slightly hard neutral to alkaline water preferred. |
