Make smarter decisions for your aquarium with our collection of free calculators and planning tools. Get instant results for tank volume, stocking capacity, water changes, and more.
🧮 Essential Calculators
Aquarium Volume Calculator
Calculate the exact water volume of your tank
Know your precise tank volume for accurate medication dosing, fertilizer calculations, and water change planning. Works with rectangular, bow-front, cylindrical, and custom-shaped aquariums.
What You'll Calculate:
- Total tank volume in gallons and liters
- Actual water volume (accounting for substrate and decorations)
- Water weight for structural planning
Implementation: free online aquarium volume calculator
Fish Stocking Calculator
Determine safe stocking levels for your aquarium
Avoid overcrowding and maintain healthy water quality. Our calculator considers fish size, bioload, filtration capacity, and territorial requirements—not just the outdated “inch per gallon” rule.
What You'll Calculate:
- Maximum safe stocking capacity
- Current bioload percentage
- Compatibility warnings
- Filtration adequacy
Implementation: free online fish stocking calculator
Features:
- Database of group-based common fish species with bioload data
- Custom fish group entry option
- Filtration strength modifier
- Planted tank bioload reduction factor
Water Change Calculator
Plan your water change schedule
Calculate how much water to change, how often, and the impact on water parameters. Optimize your maintenance routine for your specific setup.
What You'll Calculate:
- Water change volume for target nitrate reduction
- Frequency recommendations based on bioload
- Temperature-matched water volume needed
- Dechlorinator dosage required
Implementation: [Calculator shortcode]
Dosing Calculator
Precise fertilizer and medication dosing
Calculate exact amounts of fertilizers, water conditioners, medications, and supplements for your tank size. Prevent under-dosing and over-dosing.
What You'll Calculate:
- Dry fertilizer amounts (grams/teaspoons)
- Liquid product volumes (ml/teaspoons)
- Target PPM concentrations
- Multi-day treatment schedules
Included Calculators:
- NPK Fertilizer Dosing (Nitrogen, Phosphorus, Potassium)
- Micronutrient Dosing
- CO2 Injection Rate
- Medication Dosing (Common Treatments)
- Water Conditioner/Dechlorinator
CO2 & pH Calculator
Balance CO2 injection and pH levels
Determine optimal CO₂ levels for planted tanks. Calculate the relationship between CO2 concentration, pH, and KH (carbonate hardness).
What You'll Calculate:
- Dissolved CO₂ concentration (ppm)
- Target pH based on KH and CO₂ goals
- Safe CO₂ ranges for your fish
- Bubble rate recommendations
Implementation: [Calculator shortcode]
[co2_calculator]
WordPress Plugin Options:
- Calculated Fields Form
- Custom JavaScript with real-time updates
- WP Calculation Plugin
Lighting Calculator
Determine appropriate lighting for your setup
Calculate PAR levels, photoperiod recommendations, and whether your current lighting supports your plants or corals.
What You'll Calculate:
- Watts per gallon (basic metric)
- PAR at substrate level estimate
- Recommended photoperiod
- Light intensity category (low/medium/high)
Types:
- Freshwater Planted Tank Lighting
- Saltwater/Reef Lighting
Implementation: [Calculator shortcode]
[lighting_calculator type="freshwater"][lighting_calculator type=”saltwater”]
WordPress Plugin Options:
- Conditional logic forms
- Tab-based calculator interface
- Formidable Forms Pro
Heater Wattage Calculator
Size your aquarium heater correctly
Determine the appropriate heater wattage for your tank size and ambient temperature to maintain stable water temperature.
What You'll Calculate:
- Minimum heater wattage required
- Recommended wattage with safety margin
- Dual heater setup recommendations
- Monthly heating cost estimate
Implementation: [Calculator shortcode]
[heater_calculator]
WordPress Plugin Options:
- Simple calculation form
- WPForms Calculated Fields
- Everest Forms
Salt Mix Calculator (Saltwater)
Mix saltwater to the perfect salinity
Calculate how much salt mix to add for water changes or new tank setup. Achieve precise specific gravity and salinity levels.
What You'll Calculate:
- Salt mix weight needed (pounds/kg)
- Mixing instructions
- Target specific gravity verification
- Cost per water change
Implementation: [Calculator shortcode]
[salt_mix_calculator]
WordPress Plugin Options:
- Calculated Fields Form
- Custom calculator plugin
- WP Calculation Plugin
📊 Planning Tools
Tank Compatibility Checker
Check if fish species can live together
Search and select multiple fish species to check compatibility based on temperament, water parameters, tank size, and dietary needs.
How It Works:
- Search from our database of 300+ fish species
- Select the fish you're considering
- Get instant compatibility report
- See warnings and recommendations
Implementation: [Interactive tool]
[fish_compatibility_checker]
WordPress Plugin Options:
- Custom post type (Fish Species) + Search & Filter Pro
- Toolset + Custom database relationships
- Advanced Custom Fields + custom JavaScript
- FacetWP for filtering
Database Fields Needed:
- Fish name, size, temperament, pH range, temperature range, tank size minimum
- Compatibility tags/relationships
Aquascaping Layout Planner
Design your aquarium layout before you build
Visual tool to plan your hardscape and plant placement. Experiment with different layouts using the golden ratio and rule of thirds.
Features:
- Grid overlay for planning
- Drag-and-drop rocks, wood, plants
- Side-view and top-view perspectives
- Save and share your designs
Implementation: [Interactive canvas tool]
[aquascape_planner]
WordPress Plugin Options:
- Custom HTML5 canvas application
- Embedded tool using iframe
- Third-party aquascape app integration
Quarantine Tank Timer
Track your quarantine period
Set up a countdown timer for new fish quarantine. Get reminders for observation checkpoints and treatment schedules.
Features:
- 14/30/45 day countdown options
- Daily observation checklist
- Treatment dose reminders
- Email/notification reminders
Implementation: [Timer shortcode]
[quarantine_timer]
WordPress Plugin Options:
- Custom post type with date tracking
- BuddyBoss/LearnDash timer features
- Custom plugin with notification system
- Integration with email automation (Mailchimp, etc.)
Planted Tank Nutrient Tracker
Log and analyze your fertilization routine
Track your dosing schedule and plant growth over time. Identify nutrient deficiencies based on symptoms.
Features:
- Dosing log calendar
- Plant growth photo upload
- Deficiency symptom checker
- NPK ratio analysis
Implementation: [Tracking dashboard]
[nutrient_tracker]
WordPress Plugin Options:
- BuddyPress/BuddyBoss user activity tracking
- Custom dashboard with Charts.js
- GravityForms + Advanced Post Creation
- Frontend form submissions stored as custom posts
Aquarium Cost Calculator
Budget your aquarium project
Calculate setup costs and ongoing maintenance expenses. Plan your budget before you start your aquarium journey.
What You'll Calculate:
- Initial setup costs (tank, filter, heater, etc.)
- Livestock costs
- Monthly maintenance costs (food, water conditioner, electricity)
- Annual cost projection
Implementation: [Calculator shortcode]
[cost_calculator]
WordPress Plugin Options:
- Multi-step form with cost database
- Formidable Forms with pricing fields
- Calculated Fields Form with category selections
Fish Growth Predictor
Estimate adult size and growth timeline
Input current fish size and age to predict adult size and time to maturity. Plan for appropriate tank sizing.
What You'll Calculate:
- Estimated adult size
- Months to full size
- Tank size recommendations for adult fish
- Growth feeding requirements
Implementation: [Calculator shortcode]
[fish_growth_calculator]
WordPress Plugin Options:
- Database-driven calculator
- Calculated Fields Form with species data
- Custom calculation plugin
🔄 Conversion Tools
Unit Converter
Convert between measurement systems
Quick conversions for common aquarium measurements.
Conversions Available:
- Volume: Gallons ↔ Liters
- Temperature: Fahrenheit ↔ Celsius
- Weight: Pounds ↔ Kilograms
- Length: Inches ↔ Centimeters
- Concentration: PPM ↔ mg/L
- Specific Gravity ↔ Salinity (PSU)
Implementation: [Converter shortcode]
[unit_converter]
WordPress Plugin Options:
- Simple JavaScript calculator
- WP Calculation Plugin
- Custom shortcode with conversion logic
📱 How to Use These Tools
- Choose Your Tool – Select the calculator or tool you need
- Enter Your Information – Input your tank specs and parameters
- Get Instant Results – See calculations and recommendations immediately
- Save or Print – Bookmark results or print for reference
- Share – Share results with other hobbyists or store staff
💾 Save Your Results
Create a Free Account to save your calculations, track multiple tanks, and access your results from any device.
Account Features:
- Save unlimited calculations
- Track multiple aquariums
- Access calculation history
- Receive personalized recommendations
- Get maintenance reminders
📧 Get Updates
New tools and calculators added regularly. Subscribe to be notified when we launch new features.
🛠️ Technical Implementation Guide
For WordPress Developers:
Recommended Plugin Stack:
- Calculated Fields Form – Primary calculator plugin
- Advanced Custom Fields (ACF) Pro – Fish database management
- Custom Post Type UI – Create fish species/equipment CPT
- WPForms – Simple forms and data collection
- Shortcodes Ultimate – Additional UI elements
- WP Charts – Data visualization for tracking tools
Custom Shortcode Structure:
// Example structure for custom calculator shortcode
function aqualista_volume_calculator() {
// Enqueue calculator JavaScript
wp_enqueue_script('aquarium-calc-js');
// Return calculator HTML
ob_start();
include 'templates/calculator-volume.php';
return ob_get_clean();
}
add_shortcode('aquarium_volume_calculator', 'aqualista_volume_calculator');
Database Considerations:
- Custom tables for fish species data (name, params, compatibility)
- User meta for saved calculations (if user accounts enabled)
- Options table for calculator presets and defaults
Performance:
- Cache calculation results where appropriate
- Lazy load calculators below the fold
- Minify JavaScript for calculation logic
- Use CDN for calculator assets
⚠️ Accuracy Disclaimer
These calculators provide estimates based on general guidelines and common practices in aquarium keeping. Results should be used as a starting point for decision-making, not as absolute rules.
Important Notes:
- Every aquarium is unique with different conditions
- Fish behavior and bioload can vary significantly
- Water quality testing is essential regardless of calculations
- Consult with experienced aquarists or professionals for specific situations
- Calculators are educational tools, not substitutes for experience
🤝 Tool Suggestions
Have an idea for a calculator or tool that would help the aquarium community?
Email us: tools@aqualista.com
Last Updated: November 2025
Total Tools: 18 calculators and planning tools
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