The Green Journal

Fish Care Articles, Troubleshooting, and Seasonal Guides

By The Aquarium Calculators Editorial Team

Read practical fish care notes for repotting, pests, humidity, watering, fertilizer, sunlight, and beginner-friendly routines. Use header search for all 58 journal entries.

Latest Fish Care Guides

Crawlable, practical articles linked to calculators and fish entities.

CO2 regulator and diffuser in a planted aquarium
Article · 5 min

CO2 Injection for Planted Aquariums

Three different types of corydoras catfish on sand substrate
Article · 5 min

Corydoras Showdown: Julii vs. Sterbai vs. Panda – Which is Best for Your Tank?

Blue-green cyanobacteria forming slimy sheets on aquarium substrate and decor
Article · 5 min

Cyanobacteria (Blue-Green Algae): Causes & Removal

A sleek rimless nano tank on a wooden desk next to a laptop
Article · 5 min

Desk Aquariums Are Trending — Build the Perfect Nano Tank for Your Workspace

Brown diatom algae coating aquarium glass and substrate in a new freshwater tank
Article · 5 min

Diatom (Brown) Algae: Causes & How to Clear It

Multiple small breeding tanks in a rack system
Article · 5 min

Breeding Aquarium Fish for Profit

Close-up of a sick aquarium fish with visible white spots
Article · 5 min

Common Fish Diseases: Identification and Treatment

Person fishing alone at golden hour on a quiet lake
Article · 5 min

Fishing & Mental Health — Why Millions Are Heading to the Water to Unwind in 2026

Young angler holding a bass with a smartphone filming the moment
Article · 5 min

#FishTok is Taking Over — How Gen Z is Making Fishing Cool Again

Long stringy green hair algae tangled around aquarium plant stems and decor
Article · 5 min

Green Hair Algae: How to Remove & Prevent It

Hard green spot algae dots on aquarium glass surface
Article · 5 min

Green Spot Algae (GSA): Causes & How to Fix It

Aquarium with pea soup green water algae bloom obscuring fish
Article · 5 min

Green Water Aquarium: Causes & Fastest Fix

Knowledge Journey

Turn article insights into decisions with calculators, fish pages, and a quick personalized quiz flow.

Calculator

"Why Is My Fish Dying?" Diagnostic Tool

Don't panic — most fish illnesses are treatable if caught early. Select the exact symptoms your fish is showing and our diagnostic engine will identify the most likely cause, whether it's Ich, Dropsy, ammonia poisoning, or a parasite — and walk you through exactly what to do right now to save them.

Calculator

Ammonia Toxicity Calculator (Free NH3)

Enter your test kit reading (TAN), pH, and temperature — get an instant SAFE or LETHAL verdict for Free Ammonia (NH3). Built for API Master Kit users, cichlid tanks, reef setups, and fish breeders.

Calculator

Annual Fish Keeping Cost Calculator

Estimate the true annual cost of your aquarium by entering tank volume, heater wattage, filter and light power, heater runtime, and local electricity rate. Get a practical itemized breakdown for heating, filtration, lighting, water, and routine consumables before you set up, upgrade, or troubleshoot a tank.

Fish Guide

African Butterflyfish

Complete African Butterflyfish (Pantodon buchholzi) care guide. Learn optimal tank size (30-40+ gal), water parameters (pH 6.0-7.5, 75-86°F), surface feeding, breeding simulation, and compatible tank mates.

Fish Guide

African Cichlid

Complete African Cichlid (Mbuna/Peacock/Haplochromis) care guide. Learn optimal tank size (55-75+ gal), water parameters (pH 7.8-8.6, 75-82°F), Rift Lake setup, diet, and species compatibility.

Fish Guide

African Leaf Fish

Complete African Leaf Fish (Ctenopoma acutirostre / Leopard Bushfish) care guide. Learn optimal tank size (40-55+ gal), water parameters (pH 6.5-7.5, 75-82°F), carnivorous diet, and compatible tank mates.