Nano Aquarium Glossary
The water-chemistry and husbandry terms used throughout this site, defined the way keepers actually use them.
Cycle (nitrogen cycle)
The biological process where bacteria convert toxic ammonia to nitrite, then to nitrate. Establishing it before adding animals — a fishless cycle — is the non-negotiable foundation of a healthy tank.
Ammonia / Nitrite / Nitrate
The three stations of the cycle. Ammonia and nitrite should test at zero in an established tank; nitrate accumulates and is managed with water changes and plants.
KH (carbonate hardness)
The water’s buffering capacity — its resistance to pH swings. Low-KH water is unstable water, which matters double in small volumes.
GH (general hardness)
Dissolved calcium and magnesium. Critical for shrimp, which need minerals to molt properly.
TDS (total dissolved solids)
Everything dissolved in the water, read with a TDS pen. Not a substitute for KH/GH tests, but a fast drift indicator — the same instrument discipline hydroponics runs on.
Remineralization
Adding measured minerals back to RO (reverse osmosis) water to hit exact GH/KH targets. Standard practice in serious shrimp keeping.
Bioload
The waste production of everything alive in the tank. Small tanks have small bioload budgets — most stocking failures are bioload math nobody did.
Photoperiod
How long the light runs each day. The cheapest algae-control lever in the hobby, and the first one to adjust.
PAR
Photosynthetically active radiation — the light measure that matters to plants, as opposed to watts or lumens. High-PAR light without CO2 to match is an algae recipe.
Molt / Berried
Shrimp shed their exoskeleton to grow (molt); a female carrying eggs is berried. Failed molts usually point at GH/TDS problems — the parameters tell the story.
Epiphyte
Plants like Anubias and Bucephalandra that grow attached to wood or rock rather than planted in substrate. The most forgiving plant class in low-tech tanks.
Carpet
A low foreground plant grown dense across the substrate. Beautiful, and honestly: harder than the photos imply — most carpets need more light and CO2 than a beginner low-tech runs.
Diatoms
The brown algae film common in new tanks. Usually a phase that passes as the tank matures; not a product problem.
Drip acclimation
Slowly dripping tank water into the bag or container new animals arrived in, equalizing parameters over an hour or more. Standard for shrimp and sensitive fish.
Top-off
Replacing evaporated water (with RO or dechlorinated water). In nanos, evaporation concentrates everything dissolved — small tanks need top-off discipline, not occasional rescue.