Algae and plant troubleshooting: start here
Most plant problems are solved in the same order: rule out water quality, then look at light, nutrients, and carbon, changing one thing at a time. Use the checklist to narrow things down, then read the guide that matches what you see.
1. Narrow it down
Start with what you can see and what changed recently. The checklist suggests possible explanations and the safest first checks.
Plant problem checklist Tool
Tick your symptoms and recent changes to see possible explanations.
Aquarium Cycling and Water Testing for Planted Tanks Guide
Test ammonia, nitrite, and nitrate before blaming the plants.
2. Yellow leaves
Where the yellowing starts, on old leaves or new growth, is the first clue.
Why Are My Aquarium Plants Turning Yellow? Guide
Old-leaf vs new-leaf yellowing and what each pattern suggests.
Planted Tank Fertilizer Basics Guide
How plants get nutrients and how to dose without overdoing it.
Root Tabs vs Liquid Fertilizer: Which Does Your Tank Need? Comparison
Which fertilizer type suits root feeders and water-column feeders.
3. Plant melt and brown leaves
New plants often melt as they adjust to life underwater, and new tanks often get a brown film. Both are usually temporary, but established plants that brown need a closer look.
Aquarium Plant Melt: What's Normal and What Needs Fixing? Guide
What normal melt looks like and when it signals a real problem.
Why Are My Aquarium Plants Turning Brown? Guide
Brown film, brown leaves, or brown spots: what each one usually means.
4. Algae problems
Algae usually follows an imbalance between light, nutrients, and carbon. Identify the type before treating it.
Planted Tank Algae Troubleshooting Guide
Identify common algae types and what usually drives each one.
Hair Algae in a Planted Tank: Causes and a Step-by-Step Fix Guide
A step-by-step plan for green hair and thread algae.
Aquarium Light Intensity and Duration for Planted Tanks Guide
Adjust light strength and hours before adding chemicals.
5. Slow growth
Slow growth is normal in low-tech tanks. In CO2 tanks it often points to unstable carbon or too little light.
Low-Tech vs. High-Tech Planted Tanks Guide
What growth speed to expect from each approach.
Aquarium CO2 Systems Explained: A Planted Tank Guide Guide
How CO2 systems work and how to keep levels stable.