The map: every entry joined to its field and to what it measures. Tap a dot to open it.
Each dot is a question, a recipe or a lab project. Lines join it to its field and to what it measures. Click a dot to open it, or drag it.
AquariuMaker
A free library of builds for aquariums, paludariums, ripariums, vivariums, terrariums and jarrariums, each written as an experiment anyone can repeat.
Search the answers, pick an open question to run, or send your own.
In the library: 8 answered questions with papers, 13 open questions, 1 example protocol and 3 independent lab projects.
Latest:
Questions
Answered questions cite the papers that answer them. Open questions are free to claim and run.
How a recipe is written
Every recipe has the same seven parts. Go through them on the example protocol.
Read the full example protocol
Question
Do live plants speed up the nitrogen cycle in a new container?
Hypothesis
A jar with live plants reaches lower peak ammonia and nitrite, and steady nitrate sooner, than an identical jar with no plants.
Variables
- Changed
- Live plants in jar A, none in jar B.
- Measured
- Total ammonia, nitrite and nitrate in mg/L, every day.
- Kept equal
- Water volume, temperature, light, ammonia dose and jar type.
Materials
| Item | Amount |
|---|---|
| Identical glass jars | 2, about 4 L each |
| Dechlorinated water | 4 L per jar, 8 L total |
| Hornwort (Ceratophyllum demersum), or another fast stem plant that is legal where you live | 6 stems, about 15 cm, jar A only |
| Pure ammonia solution, no scent or detergent | Enough to dose 2 mg/L |
| Liquid test kit for ammonia, nitrite and nitrate | 1 |
| Aquarium thermometer | 2, one per jar |
| LED lamp on a timer | About 800 lumens, 8 h a day |
| Logbook or spreadsheet | 1 |
Method
- Label the jars A and B. Fill each with exactly 4 L of dechlorinated water.
- Put the 6 stems in jar A only. Jar B stays water only.
- Set both jars under the same lamp, 20 to 25 cm away, on a timer for 8 hours a day.
- Add ammonia to each jar until both read 2 mg/L. Stir gently.
- Once a day at the same hour, test total ammonia, nitrite and nitrate in each jar. Record every value and the temperature.
- When ammonia reads 0, dose it back to 2 mg/L.
- Run for 6 weeks, or until a jar takes 2 mg/L of ammonia to 0 ammonia and 0 nitrite within 24 hours.
- On the last day, take the plants out of jar A. Dose both jars to 2 mg/L and test again 24 hours later. This separates what the bacteria remove from what the plants were taking up.
Data to record
| Day | Temp °C | TAN A | TAN B | NO₂ A | NO₂ B | NO₃ A | NO₃ B |
|---|---|---|---|---|---|---|---|
| 1 | |||||||
| 2 | |||||||
| 3 |
TAN is total ammonia (NH₃ plus NH₄⁺), which is what most hobby test kits read. Use the same kit for every reading and write down the units it reports.
The science
Nitrifying microbes turn ammonia into nitrite, then nitrite into nitrate. One group, comammox Nitrospira, does both steps in a single cell. Plants add a second route: they take up ammonium and nitrate directly, and they release oxygen that nitrifiers use.
Reading the result
If jar A shows lower peak ammonia and nitrite and reaches steady nitrate first, the hypothesis is supported. If the two jars track together, it is not. Step 8 shows how much of the difference came from the bacteria and how much from the plants.
Send a recipe
The library is built from what makers send in. A plan is enough to start. Data can come later.
- 1
Pick an open question on the map, or bring your own.
- 2
Send it with this form, with a link to your method, data or photos if you have them.
- 3
Every submission is read and its method checked. When it is ready, it goes on the map with your name.
- 4
Other makers run it and send their data. Each run is added to the same recipe.
The form asks for a name, an email, the question and how far along it is. A method, data and links are optional.
- No likes, follower counts or trending lists.
- Linking your own profile is optional.
- Beginners are welcome. Be precise and be kind.
Independent lab
AquariuMaker is run by Impossible Aquariums, an independent home lab with planted tanks, jars and a microscope. Three of its projects are in the library.
Its projects in the library
Under the lab microscope
Support it
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Run a recipe and send your data.
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Frequently asked questions
What is AquariuMaker?
A free library of aquarium, paludarium, riparium, vivarium, terrarium and jarrarium builds written as experiments. Each entry states a question, the materials, the method and what to measure, so anyone can repeat it and compare results.
Is it free?
Yes. There are no accounts, no ads and no paid tiers.
What is the difference between an answered question and an open question?
An answered question already has an answer in published research. Its card gives the short answer, what the papers found and a link to each paper. An open question has no settled answer yet; anyone can claim it and run it.
Where do the answers come from?
Only from peer-reviewed papers, each linked by DOI or PubMed Central. Books, videos and forum posts are named only as the place a question comes from, never as the answer.
What is a recipe?
An experiment written so someone else can repeat it: one question, a hypothesis, what changes and what stays the same, exact materials, numbered steps and the data to record. The example protocol above shows the format.
How do I claim an open question?
Open its card or its dot on the map and choose Claim this question. The form fills in the question; add a name, an email and how far along you are, then send it.
Do I need lab equipment?
Most questions need hobby gear: a liquid test kit, a thermometer, a scale or a ruler. Each entry lists what it measures and a level, Beginner or Intermediate. A few need more, such as a microscope or a moisture meter.
What happens after I send a recipe?
Every submission is read and its method checked. When it is ready, it goes on the map with your name. Other makers can run the same recipe, and each run is added to it.
Will my name and data be public?
Only if you tick the permission box on the form. Email addresses are not published, and a profile link is optional. The privacy policy covers both AquariuMaker and Impossible Aquariums.
How often will I get emails?
One email each time a new recipe goes up, plus a reply to anything you send.
Can I suggest a question that is not on the map?
Yes. Use the recipe form and write your own question. A plan is enough to start.
Who runs AquariuMaker?
Impossible Aquariums, an independent aquarium lab in Florida. Its own projects are marked Independent lab on the map.