Aquarium Maintenance Schedule, Checklist & Test Log

Make a printable aquarium maintenance checklist

Choose your tank and routine, then print or download one page. A saved tank fills in its water type and actual system water volume. The starting example is 200 L with a 25% change every 7 days; replace it with your own plan. Use measured nitrate production to choose a freshwater change interval.

This plan replaces more than half the water. Check replacement-water chemistry and livestock needs before using it; a large change is not an automatic catch-up routine.

What aquarium maintenance should I do daily, weekly and monthly?

A daily look catches the things a calendar cannot: unusual breathing, a stopped pump, falling water level or a heater behaving differently. Observe feeding and remove food that is left behind. Check temperature against the tank’s usual reading and make sure the filter is moving water.

Use a weekly appointment to review the tank, record the tests that matter, clean viewing glass and decide which jobs are due. The Merck maintenance checklist separates daily observation from less frequent cleaning and makes water-change volume dependent on stocking. Our weekly review is a reminder to assess those jobs, not an instruction to perform all of them.

Monthly, inspect the equipment you own: intakes, hoses, impellers, heater condition, timers and test-kit supplies. Check the manufacturer’s servicing and calibration instructions. A dirty pump may need attention sooner; a calendar date alone does not tell you that biological media needs replacing.

What order should I follow on water-change day?

1. Prepare the replacement water. Use dedicated, soap-free containers. Match temperature and appropriate chemistry. Treat chlorinated tap water; for marine tanks, mix and verify saltwater before use.
2. Test and write down the baseline. Mark it “before change.” A nitrate reading taken immediately afterward cannot be compared fairly with last week’s pre-change peak.
3. Make equipment safe. Follow the manuals for switching off heaters and pumps before the water falls below their operating level. Keep biological media wet.
4. Clean what needs cleaning and remove the planned volume. Siphon accessible debris; work around plant roots and avoid disturbing an entire established deep substrate bed.
5. Refill, restart and verify. Check temperature, marine salinity, circulation, leaks and equipment operation. Record the actual amount changed, any product added and anything unusual.

For marine preparation details, use the salt-mix calculator and mixing instructions. For a nitrate problem, use the reef water-change tool or freshwater water-change tool to check what dilution can achieve.

How much water and conditioner belongs on my checklist?

The percentage applies to the water actually in the system, including an operating sump and allowing for displacement. For the 200 L example, a 25% change is 50 L. This table uses that same fraction and the standard metric Prime label rate, with the replacement water treated in a separate container.

Computed from system liters × change fraction and Seachem’s 5 mL per 200 L directions. The chosen 25% is an example, not a universal weekly prescription.

Other products have different concentrations and instructions, including separate chlorine and chloramine rates. Use the appropriate rate on your bottle. The sheet uses Prime’s standard rate; its label has special instructions for unusually high chloramine and water over 30 °C. For those conditions, consult the full directions. Measure small doses with a suitable syringe; do not round a tiny dose up to a capful.

How do I keep an aquarium water-test log that is useful?

Write the date and time above each test column. Record the reading in the printed unit, and put “not tested” or a dash where you skipped a test. For results below a kit’s detection limit, record that limit instead of inventing a precise zero. Note whether you sampled before or after a water change, feeding or dosing.

The reference column comes from our freshwater parameter presets or reef presets. These are broad editorial ranges, not species guarantees or instructions to adjust water to the midpoint. Reef nutrient preferences vary substantially between methods; Randy Holmes-Farley’s parameter discussion gives a different, wider nutrient range. Use the targets appropriate to the animals and method you have chosen.

New tanks and tanks recovering from filter disruption need closer ammonia and nitrite monitoring than an established system. An established reef needs particular attention to alkalinity consumption. Use the linked parameter guides to set testing frequency; the three columns are recording spaces, not three scheduled tests. Keep old sheets so gradual drift stays visible.

What changes for planted, saltwater and reef aquariums?

Planted: trim according to growth and remove loose cuttings. Tropica recommends small, frequent trims over an occasional severe cut. Check the fertilizer routine after changing plant mass or lighting. If you inject CO2, include the timer, supply and drop checker in observation, but watch livestock too: an indicator is not an instant oxygen monitor. Use your EI routine or bottled fertilizer plan for dosing and its associated water changes.

Saltwater: replace evaporation with fresh RO/DI water; replace removed saltwater with prepared saltwater. If fitted, inspect the auto top-off reservoir and sensor, and check the skimmer before its cup overflows. The BRS marine checklist is a useful inventory of those extra jobs, but equipment and media schedules still depend on the system.

Reef: add alkalinity, calcium and magnesium records. Test alkalinity more often while establishing demand or changing a dosing routine, and inspect dosing lines and stock if used. Take dosing amounts from measured consumption with the two-part calculator; the maintenance sheet deliberately leaves the dose off until you have established that demand.

I missed maintenance—or the fish look wrong. Should I just do a bigger clean?

Start with observation and testing, not a doubled cleaning session. Check temperature, flow, water level and the relevant water-quality readings. Compare current and replacement-water chemistry before making a large change, especially after a long lapse. A sudden correction can be another major change for the livestock.

Unusual breathing, loss of balance or widespread distress needs attention now, regardless of the next date on the sheet. Check aeration and equipment immediately and use the ammonia assessment and parameter guides to interpret readings. Do not replace all filter media or scrub every surface as a catch-up task. Record what happened, the action taken and the follow-up reading so the next decision has evidence behind it.