A Planted Tank Maintenance Routine

A maintenance routine exists to keep conditions steady. Plants and animals cope well with stable conditions and poorly with sudden swings, and most problems in planted tanks start small: a few decaying leaves, a clogged filter, a drifting timer. A regular routine catches these early, while they are still easy to fix.

The right frequency depends on your tank. A slow-growing, low-tech tank with Anubias and cryptocorynes needs far less work than a high-light tank with injected CO2 and fast stem plants. If you are not sure which type you have, low-tech vs. high-tech planted tanks explains the difference.

The routine at a glance

The frequencies below reflect common hobby practice, not fixed rules. Use them as a baseline, then adjust.

How much water should you change in a planted tank?

Water changes remove dissolved waste and reset nutrient levels. Tropica's care guidance notes that changing about 25 percent of the water every week prevents the build-up of harmful substances and limits algae growth.

How to do it:

1. Unplug the heater and, if needed, the filter.
2. Siphon water from the substrate surface, collecting debris as you go.
3. Prepare new water with a dechlorinator and match the temperature closely.
4. Refill gently so you do not uproot plants or cloud the water.
5. Restart equipment once the heater and filter intake are fully submerged.

Low-tech tanks with few animals can often stretch to every two weeks. CO2 tanks with heavy fertilization usually benefit from a weekly change, because nutrient levels build up faster.

Trimming and plant cleanup

Tropica's trimming guidance favors small, frequent trims over large ones, since removing a lot of plant mass at once can upset the tank's balance. Remove leaves that shade the surface or neighboring plants, and pull out dead or melting leaves. Tropica's care guidance calls for removing decaying plant matter quickly, because its breakdown uses oxygen and produces nutrients that encourage algae.

Fast stem plants in CO2 tanks may need weekly attention. Slow plants in a low-tech tank may go weeks without a trim. How to trim stem plants covers technique, and essential aquascaping tools covers the scissors and tweezers that make it easier.

Glass cleaning

Wipe the inside glass with an algae pad or scraper before your water change, so loosened algae and debris go out with the old water. Be careful near the substrate, since sand or gravel caught in a pad can scratch glass and acrylic. A light film every week is normal. Rapid regrowth is a sign to look at light, nutrients, or CO2 rather than scrubbing harder. Planted tank algae troubleshooting can help.

How do you clean the filter without losing the cycle?

Clean the filter when flow drops noticeably, or on a regular monthly schedule. The goal is to clear trapped debris without removing the bacteria that process ammonia.

• Rinse gently. Swish or squeeze sponges and media in a bucket of water removed during the water change. Many keepers prefer this as a conservative habit. Aquarium Science argues that the chlorine in tap water is not the real risk and that vigorous scrubbing under running water does more harm, so whichever water you use, keep the rinse gentle.
• Do not clean everything at once. If your filter has several media stages, rinse one at a time across different weeks.
• Check the intake and impeller. Plant trimmings and snails can block intakes and slow impellers.

The planted aquarium filter guide explains filter types and flow, and the filters hub lists categories.

When should you dose fertilizer?

Many keepers dose a weekly fertilizer just after the water change, so the fresh water starts with a known nutrient level. CO2 tanks with fast growth often use smaller doses spread across the week. Tropica advises starting with a smaller dose than recommended and increasing gradually based on how the plants respond. Pale or transparent new leaves can point to a deficiency. Planted tank fertilizer basics explains how to build a routine.

How often should you test the water?

Testing confirms what your eyes suggest. In an established, stable tank, a monthly check of ammonia, nitrite, nitrate, and pH, plus hardness if you keep sensitive animals, is a common baseline. Test more often in a new tank, after adding animals, after a large trim, or whenever plants or animals look wrong. Aquarium cycling and water testing covers what each reading means, and the test kits hub lists the kit types.

Equipment checks

CO2 system

For pressurized CO2, check the cylinder pressure, bubble rate, and fittings weekly, and watch your fish for signs of stress such as gasping at the surface. Aquarium Co-Op points out that plants only use CO2 while the lights are on, and suggests starting CO2 one to two hours before the lights and stopping it about an hour before lights out. The aquarium CO2 system guide covers setup and adjustment, and the CO2 systems hub lists the components.

Timer and lights

Power cuts and daylight saving changes can shift digital and mechanical timers. Confirm the light schedule and, in CO2 tanks, that the CO2 still starts and stops in step with it. Aquarium timers and lighting schedules covers scheduling, and the timers hub lists options.

Heater

Glance at the thermometer every few days. A reading that drifts away from your target suggests a failing heater or a change in room temperature. Always unplug the heater before lowering the water level.

Common mistakes

• Skipping water changes when the tank looks fine. Waste builds up before it becomes visible.
• Cleaning everything on the same day. A full filter clean, a deep gravel vacuum, and a heavy trim together can unsettle the tank.
• Scrubbing filter media hard. Gentle rinsing keeps more of the beneficial bacteria.
• Leaving trimmings and dead leaves. Decaying material feeds algae.
• Dosing on autopilot. Fertilizer needs change as plants grow in or are cut back.
• Ignoring equipment until it fails. A quick weekly check catches drifting timers and leaking fittings.
• Following a schedule rigidly. Watch your tank and adjust.

Next steps

• Build a fertilizer plan with planted tank fertilizer basics.
• Learn what your test results mean with aquarium cycling and water testing, and compare water test kits for planted tanks.
• Find siphons and magnetic glass cleaners for routine upkeep in our aquascaping and maintenance tools.
• Keep stem plants dense with how to trim stem plants.
• Tune your CO2 setup with the aquarium CO2 system guide.
• Match equipment to your tank with the setup finder.