New to Your Home · Aquatic
Aquarium Nitrogen Cycle
Balancing Water Chemistry and Preventing Tank Crashes
Clear water in a brand-new tank can still harm fish within days, and this course explains why. 10 lessons on New Tank Syndrome, the ammonia spike and why pH and temperature change how toxic it is, the nitrite phase and brown blood disease, nitrate and how to keep it in check, humane fishless cycling, what bottled bacteria can and cannot do, reading a liquid test kit, where beneficial bacteria live in your filter, preventing a mini-cycle when you clean, and the triage steps for a crashed cycle.
About this course
A new tank full of fresh, dechlorinated water looks ready for fish, but it has none of the bacteria that clean up after them. This course starts there, with New Tank Syndrome and why fish added on day one can be harmed within days. Then you follow the cycle step by step: where ammonia comes from and why the same reading is far more dangerous in warm, alkaline water; how bacteria turn ammonia into nitrite, and how nitrite stops blood from carrying oxygen; and how a second group of bacteria turns nitrite into nitrate, which you keep under about 20 to 40 ppm with water changes. Lesson 5 walks you through fishless cycling with ammonia, including how to know the cycle is done. Lesson 6 sorts out bottled bacteria: which products contain live nitrifying bacteria, why they need ammonia to eat, and why borrowing media from a healthy tank works so well. You'll learn to use a liquid test kit properly, including the nitrate bottle that needs a hard shake, and where your bacteria live in the filter. The last two lessons cover how to clean without setting off a mini-cycle, and what to do, step by step, if the cycle crashes.
What you'll learn
- Why a brand-new tank can harm fish, and what New Tank Syndrome is
- Where ammonia comes from, how pH changes its toxicity, and how nitrite causes brown blood disease
- Keeping nitrate in check, and humane fishless cycling with ammonia to 2 ppm
- What bottled bacteria can and cannot do, and seeding with media from a healthy tank
- Reading a liquid test kit correctly, and where beneficial bacteria live in your filter
- Preventing mini-cycles when you clean, and step-by-step triage for a crashed cycle
Who this is for
Beginners setting up their first aquarium who want it ready before they buy fish; keepers who lost fish in a new tank and want to understand why; and anyone whose ammonia or nitrite readings jumped after cleaning the filter.
Course outline (10 modules)
Quiz & Certificate
Knowledge quiz
After completing all lessons, take a short quiz to test your understanding.
Go to quiz →Completion certificate
Pass the quiz and earn a shareable certificate of completion.
View certificate →Frequently asked questions
Ready to get started?
$9.99 · Lifetime access · 10 lessons