Finfern honest freshwater care

🩺 Your free vet-prep sheet

Your Glowlight Danio Vet-Prep Sheet

Fish vets are rare, and it is easy to freeze in a crisis. This is the one page to have ready — how to find a vet, what to bring, what to tell them, and the questions to ask. Print it and keep it by the tank.

Black & white saves ink and prints cleanly on any printer.

Not sure it's a vet trip yet? Run the symptom checker or the water-parameter interpreter first — many worries turn out to be a water or husbandry fix.

Finfern honest freshwater care · finfern.com
Glowlight Danio — Vet-Prep Sheet

🔍 Find an aquatic / fish vet — before you need one

  • Search the WAVMA aquatic-vet finder (the World Aquatic Veterinary Medical Association) — or search "aquatic / fish / exotics vet near me".
  • Call ahead and ask the key question: "Do you treat fish?" Few vets do — and ask the exam fee while you're on the phone.
  • Find and save one now, while things are calm — not in the middle of a crisis.

📇 Fill this in now — before the crisis

Two minutes now saves ten in a panic. Print it and keep it by the tank.

My fish vet
My glowlight danio
What I'm seeing

🚨 Is this an emergency now?

Act promptly — starting with a water test — if you notice any of these:

  • Fish gasping at the surface, clamped fins, or sudden lethargy: stop feeding and test the water immediately for ammonia, nitrite and nitrate; a spike (usually from an un-cycled or overstocked tank) is the most common cause, so do a water change and re-check.
  • Faded colour, hiding, and flicking/darting against decor: often a sign of stress from too-small a group, poor water, or too much flow; check the shoal size, parameters and current before assuming disease.
  • Persistent chasing with torn or ragged fins: the group is likely too small or the tank too short; add numbers and swimming length so aggression disperses.
  • White spots, cottony patches, or rapid breathing in several fish: treat as a possible outbreak, quarantine if you can and seek advice from a fish-savvy vet or a trusted aquatic source. This is triage, not a diagnosis, get eyes on the fish.
  • A missing fish: check the floor and behind the tank; they jump, so confirm your lid has no gaps.

When in doubt, a vet call is never wrong — most issues are reversible if caught early.

🚗 On the way / while you wait

✅ Do

  • Test your water NOW — ammonia, nitrite, nitrate, pH and temperature — and correct the obvious (a big source of trouble is ammonia / nitrite).
  • Keep the fish in its own stable, dechlorinated tank water.
  • Move it to a hospital / quarantine tank if you already have one set up.
  • Keep the tank calm and dimly lit — stress makes almost everything worse.

⛔ Don’t

  • Don’t tip in OTC, aquarium-shop or forum “cures” blindly — many are harmful or just mask the real problem.
  • Don’t make a big sudden water change or swing the parameters.
  • Don’t add salt or medication without knowing the cause.

🎒 What to bring

  • A recent water-test result — ammonia, nitrite, nitrate, pH and temperature. Water quality is the root of most fish illness and the first thing a fish vet asks about.
  • Clear photos and a short video — it may not show the behaviour or symptom in the clinic.
  • A note of your setup and exactly what — and how often — you feed.
  • Only if the vet advises transporting the fish: the fish in a bag or tub of its OWN tank water.

🗣️ What to tell the vet

A general vet may not know this species. Come ready to explain its correct care:

Temperature
SeriouslyFish gives 16-26 °C (61-79 °F). It prefers warmer, stable water — around 23-25 °C (73-77 °F) is ideal, and wild fish were recorded at ~24.8 °C — but it tolerates cool-to-subtropical conditions down to ~16 °C, so a heater is sensible for stability rather than strictly essential.
pH
6.0-7.5 (tolerates up to about 8.0). Stable is more important than chasing a number.
Hardness
Soft to moderately hard: roughly 1-12 dGH (most guides land in the 2-12 dGH band).
Minimum tank
Keeper-facing minimum for a proper shoal is around 60 L (roughly 16 US gal) with a footprint of at least 60 cm (24 in) of swimming length. SeriouslyFish sets the bar at an 80 x 30 cm base (about 72 L / 19 US gal). You will see 38 L / 10 US gal "nano" minimums quoted, but the reality is that swimming length matters more than raw volume for these restless, fast little fish, and bigger is calmer, so treat 60 cm of length as the real floor and go longer if you can.
Filtration & flow
Gentle to moderate flow suits their hill-stream origin. They like well-oxygenated water and a little movement, but not a washing-machine current; aim the filter return along the glass or spread it so there are calm zones and a flowing lane.
Diet
Omnivore, insectivore-leaning in the wild. Takes most prepared foods; colour and condition improve with small live/frozen items.
Tankmates / temperament
Peaceful and active. Males spar and set up a gentle pecking order, which is normal; a big enough group spreads that energy out so no single fish gets picked on.

⚕️ Most fish illness starts with water quality, not infection — bring a recent water test; it's the first thing a good fish vet will ask about. Fish medicine is specialised and few vets treat fish, so call ahead. Many aquarium-shop and OTC 'cures' are harmful or simply mask the real problem, so tell the vet exactly what (if anything) you’ve already added, and treat a sick fish in a separate hospital tank rather than dosing the whole display.

Then note which of the warning signs (above) you are seeing, when they started, and whether they are getting worse.

❓ Questions to ask

  • Do you treat fish? If not, can you refer me to a vet who does?
  • What are the likely causes — and could my water or setup be the cause?
  • What is the treatment plan, the likely cost, and what should I watch for at home?
  • How do I prevent this from happening again?