Setup path, after stage 10
Reef tank maintenance schedule for the first year
What to do each day, week, month and half year, how often to test as the tank matures, and when to decide on a dosing method. Written for a new mixed reef; adjust as your tank tells you.
Last checked . How we check
What happens week by week in the first six months?
| Weeks | What you do | Move on when |
|---|---|---|
| Before week 0 | Plan, buy kit, place and leak test | Stand level; fresh water test dry for 24 to 48 hours |
| 0 | RO/DI, mix salt, heat, rock and sand, flow | Salinity and temperature steady for 24 hours |
| 0 to 2 | Cycle with bacteria and ammonia (4 to 8 weeks without bacteria) | Ammonia 2 ppm to 0.25 ppm or less in 24 hours, twice |
| 2 to 3 | Water change if nitrate is high; light on a modest schedule; first snails | Ammonia and nitrite zero; diatoms are normal |
| 3 to 6 | First one or two quarantined hardy fish; feed lightly; weekly nitrate and phosphate | Readings steady for two weeks |
| 6 to 10 | First hardy soft corals at low light | Corals open; nutrients measurable |
| 10 to 16 | More fish in small groups, two weeks apart; weekly calcium, alkalinity and magnesium | You can measure alkalinity use |
| 16 to 26 | LPS; start dosing if water changes no longer hold alkalinity | Alkalinity steady within 0.5 dKH a day |
| 26 onwards | SPS only once alkalinity, calcium and magnesium have held for months | Stable weekly logs |
What should I do every day, week and month?
| How often | Jobs |
|---|---|
| Daily | Look at every fish and coral; check temperature on a second thermometer; check the top-off reservoir and sump level; feed; empty the skimmer cup if it is wet; glance at doser bottle levels. |
| Weekly | Water change (10% is common); tests below; clean the glass; change filter socks or floss (every two to three days is common); wipe the ATO sensor. |
| Monthly | Check the refractometer with 35 ppt fluid; clean the skimmer neck; calibrate dosing pumps; calibrate any pH probe; force each heater controller to switch to prove it works; harvest any refugium (Triton says every two to four weeks); replace carbon or phosphate remover as used. |
| Every three months | Clean wavemakers and the return pump. |
| Every six months | Change RO/DI prefilters (typical); test how long the battery backup runs; replace any heater past its rated life. |
How often should I test reef water?
| Test | New tank | Established mixed reef | SPS tank |
|---|---|---|---|
| Salinity | Daily | Every few days and after top-ups | Same |
| Temperature | Always on display | Always on display | Always on display |
| Ammonia and nitrite | Daily or every other day while cycling | When adding stock or something looks wrong | Same |
| Alkalinity | Two or three times a week | Weekly | Daily or every other day |
| Calcium | Weekly | Weekly | Twice a week |
| Magnesium | Weekly | Every two weeks | Weekly |
| Nitrate and phosphate | Weekly | Weekly | Weekly, more often with phosphate remover or an algae reactor |
| pH | Weekly | Weekly; more with kalkwasser or a reactor | Same |
| Potassium and iodine | Not needed | Monthly if you dose them | Monthly |
| ICP lab test | Not needed | Optional | Every two to three months (Triton) |
Test at the same time of day each time: Red Sea notes alkalinity readings move through the day. BRS's own 600 litre display tank tests alkalinity daily, calcium weekly and magnesium monthly, and nitrate and phosphate only when something looks off, which shows how much routines vary once a tank is stable.
When should I start dosing?
When water changes no longer hold alkalinity. Reef Builders suggests dosing only once alkalinity, calcium or magnesium fall below natural seawater levels (about 7 dKH, 400 ppm and 1200 ppm) and logging daily tests for a week first, so you know how much the tank uses. Red Sea's method is similar: bring the numbers to target, stop dosing for four days with salinity held steady, and divide the drop by four for the daily need. Then choose a method from methods compared. The daily consumption and dosing calculators do the arithmetic.
What are the common mistakes?
- Testing only when something looks wrong, so there is no normal to compare with.
- Big corrections in one go: Red Sea caps daily rises at about 1.4 dKH, 20 ppm calcium and 10 ppm magnesium.
- Changing several things in one week, then not knowing which one helped.
- Letting test reagents go out of date.
- Skipping the monthly heater controller check.
Where do sources disagree?
| Topic | What sources say | Our reading |
|---|---|---|
| Water changes |
| About 10% a week for a first tank, whatever the method. |
| How often to test alkalinity once stable |
| Weekly for soft corals and LPS; two or more times a week once stony corals are growing fast. |
See also: Holidays and sitters, Emergencies, Water change calculator.
Sources
- Charterhouse Aquatics, what to test in a reef aquarium and how often
- BRS, what it takes to maintain the BRS160 reef tank (FAQ 34)
- Reef Builders, Fauna Marin Balling Light instructions
- Triton, the Triton Method
- Triton, frequently asked questions
- Reef Builders, how and why to dose your reef tank
- Red Sea, Foundation testing and supplementing manual (v21a)
- Red Sea, Complete Reef Care four-part manual (V24A)
- BRS, preparing your aquarium for a holiday
Figures from sources read as a search summary only are shown as typical figures: check them before you rely on them. Found a mistake? Tell us how to fix it.