Goldfish Buying Guide
Goldfish have been beloved in Japan for centuries. With many varieties available, they're enjoyable for beginners and enthusiasts alike. This guide covers what to know before purchasing goldfish.
💰Price Range
Common Goldfish $1-$5, Ryukin $5-$30, Ranchu $30-$500
View detailed price data →Recommended for Beginners
Buying Tips
Get a larger tank
Goldfish grow, so prepare at least a 45cm (18in) tank.
A filter is essential
Goldfish are messy — a strong filter is necessary.
Match body types for tankmates
Slim and round types swim at different speeds. Keep them separate.
Acclimate when introducing
Float the bag in the tank to match temperature, then slowly mix water.
Useful Tools
💧 Aquarium Volume Calculator
Calculate water volume, weight, and heater wattage from tank dimensions
🧪 Water Quality Checker
Find compatible fish, shrimp, plants & corals based on pH, temperature & hardness
🍽️ Feeding Guide
Check feeding frequency, portion sizes & supplements by species and growth stage
🤝 Compatibility Checker
Check compatibility between two species on a 5-level scale
📊 Fish Compatibility Matrix
Check fish compatibility at a glance with our matrix chart
🗓️ Seasonal Care Calendar
Monthly care events and seasonal management tips at a glance
🚿 Water Change Calculator
Auto-calculate optimal water change frequency and volume by tank size and fish count
🐠 Stocking Calculator
Calculate max fish capacity for your tank size with overstocking alerts
🧬 Breeding Planner
Select parent varieties to view breeding schedules and offspring patterns
🏞️ Tank Layout Planner
Get substrate, plant & hardscape suggestions based on tank size and style
🧮 Care Cost Simulator
Estimate initial, monthly & annual costs by category, care level and quantity
⚖️ Species Comparison Tool
Compare two species side by side: care difficulty, size, lifespan & temperature
🎯 Pet Match Diagnostic
Answer 7 questions to find your top 3 perfect pets
📋 Lifetime Cost Simulator
Estimate lifespan and lifetime costs by species for dogs, cats, reptiles and more
🚚 Transport Safety Checker
Check transport safety score and precautions by category, season, method and distance
💊 Medication Dosage Calculator
Calculate proper medication dosage by body weight and medicine type for fish, reptiles, and small animals
Related Content
If you have questions about care, you can ask experienced keepers and breeders on the Care Q&A Board. If you notice health issues, try the Find by symptom.