Aquarium maintenance schedule

A tank that stays running is a tank with a boring schedule. You do not deep-clean everything on the same Saturday. You change water, you glance at the fish, and you leave the filter bacteria alone unless they are clogged.

Daily (30 seconds)

• Are the fish swimming, or pinned in a corner?
• Is the heater on and the temperature in range?
• Is the filter making the usual noise, not a dying rattle?
• Any jumpers on the floor? Lid closed?

If someone is gasping, skip the rest of this page and test ammonia.

Weekly

Default for a stocked community: about 25% water change. Goldfish and overstocked tanks want more. Lightly stocked planted tanks can do less if nitrate stays in check — test, do not guess.

1. Test nitrate (and ammonia if the tank is new or something died).
2. Use the water change calculator for gallons removed and conditioner mL.
3. Match tap temperature within a couple of degrees.
4. Vacuum the obvious mulm. Do not stir every inch of sand every week if you have corys.
5. Wipe the front glass. Leave the back dirty if it does not bother you — algae there is a snack for shrimp.

Feeding is daily, but it belongs in the feeding guide. Two minutes of food. Not a banquet.

Monthly

• Rinse mechanical filter media in old tank water, not tap.
• Check the heater’s actual temperature with a second thermometer.
• Trim plants before they shade everything and melt in the back.
• Glance at stocking. Juveniles grow. Run stocking if the school doubled itself.

Do not do on the same day

• Replace all filter media.
• Scrub every decoration.
• Change 70% of the water.
• Add five new fish.

That combination is how you crash a cycle. Pick one disruption.

Lighting

Most planted tanks want 6–8 hours, not dusk-to-dawn. Algae loves a 14-hour photoperiod. See light schedule and the lighting calculator.

When the schedule slips

If you missed two weeks, do a water change and a test, not a punishment 80% siphon. Then go back to weekly. The maintenance vs algae note is the other half of this page.