How to Take Care of a Planted Aquarium Week by Week
As an Amazon Associate we earn from qualifying purchases.
How to take care of a planted aquarium comes down to a short routine: run the light on a timer, change water to keep nitrate and algae down, trim plants into shape, and feed the roots of plants that need it. The three pages used for this guide give clear advice on light hours, root tabs, algae and trimming, but none gives a fixed water change schedule. This page builds a week-by-week routine from what they do say and marks the places where you must watch your own tank.
Quick answer
- Light: start with 6 to 8 hours a day on a timer and never leave it on overnight (Aquarium Co-Op).
- Root feeding: push a root tab into the substrate about every 5 to 6 inches for plants that feed through their roots (Aquarium Co-Op, and the product listing below).
- Algae: regular water changes lower nitrate, and balancing light, nutrients and plant growth keeps algae down (Wikipedia).
- Trimming: plants are trimmed to shape the layout, and some styles deliberately leave them untrimmed (Wikipedia).
Week one: set the light and watch
The first week is mostly about the light schedule. Aquarium Co-Op advises starting a new planted tank at 6 to 8 hours per day and using a timer so the schedule stays steady. It also says not to leave the light on overnight, even in moonlight mode, because plants need a dark period for respiration. Keep the tank out of direct sunlight, which the guide says fluctuates and makes light control harder.
For brightness, the same guide suggests starting around 20 to 40 percent if your light dims, and raising it only if algae does not appear. A light that cannot dim can be raised above the tank or partly covered with black tape. Write down your starting hours and brightness. The guide recommends keeping a log of settings.
In this week, do not change several things at once. The guide says to change one variable at a time and wait about two weeks between changes, at least in low-tech tanks without CO2 injection. If you are tempted to add fertilizer, a new plant and a longer light period on the same day, pick one.
Week two: first root feeding and the first trim
If your plants root in the substrate, this is a good time to think about root tabs. Aquarium Co-Op describes them as dissolvable fertilizer tablets for plants that feed mainly through their roots. Push each tab deep into the substrate, ideally beneath the roots, using planting tweezers or your fingers. A tab that floats to the surface is harmless, the guide says. Space tabs roughly every 12 to 15 cm (5 to 6 inches) in a grid, or closer, about 10 cm (4 inches) or less, in a dense tank. Large plants such as Amazon swords may need several tabs in a ring around the base.
The guide lists the plants that benefit most as cryptocorynes, sword plants, bulb plants, carpeting plants and plants that send out runners. It says stem plants such as bacopa and moneywort mostly feed from the water, and that mosses, floating plants, anubias and java fern rarely need root tabs. So check what you have before buying.
For the first trim, Wikipedia says plants are trimmed to shape the design, which is most visible in neat Dutch-style groupings, while jungle-style aquascapes deliberately leave plants untrimmed for a wild look. Decide which look you want. In a small betta tank a light trim of tall stems keeps open swimming space.
Week three: water changes and algae check
Wikipedia explains that algae is most often caused by excess nutrients and waste, and that water changes lower nitrate, which helps prevent algae. The article gives no water change schedule, and neither do the Aquarium Co-Op pages used here. So the interval is something you set by watching your tank. If algae appears, the sources point to the same pair of fixes: lower the light (hours or brightness) and keep up the water changes.
The article also lists other methods: algae-eating animals such as certain shrimp and snails, and balancing light, CO2 and nutrients so that plants grow quickly and use up the nutrients algae would feed on. Before adding any algae eater to a betta tank, check compatibility with the fish, and ask a fish vet or an experienced keeper if you are unsure.
In low-tech setups, fish waste serves as fertilizer, according to the same article. That means feeding and stocking affect plant growth. A tank with few fish and many plants may need root tabs, while a heavier stocking level supplies more by itself. The sources do not give a ratio, so watch the plants: stunted growth, yellowing or browning, and melting leaves on plants that previously grew well can show that the substrate nutrients are running low, according to Aquarium Co-Op.
Week four and onward: a monthly rhythm
Aquarium Co-Op says to add root tabs about once a month, especially in inert substrates such as gravel or sand, and notes that growing plants need more over time. Its example is a newly planted Amazon sword needing one tab every six weeks but later up to six per month. Product makers give different advice. The root tab listing below says nutrients release over 2 to 3 months and suggests replacing every 2 to 4 months or as needed. Because the two differ, start at the lower dose and let plant growth tell you whether to add more.
Each month, also review the light log. If plants grew well and no algae appeared, you could raise the hours toward the 8 to 12 hours the guide mentions for established tanks. If algae appeared, shorten the period. Trim again if tall plants shade smaller ones.
Wikipedia adds that new plants can carry algae, snail eggs or worms, so aquascapers often dip them in diluted hydrogen peroxide or bleach before adding them. That is a stronger step than most betta keepers need, and the article gives no dilution, so use a plant seller’s instructions if you try it.
A product that fits the root-feeding step
The pack for this post includes two listings of the same root tab product, one with 100 tabs and one with 200 tabs. Both describe a fertilizer for aquarium plants that is safe for fish and shrimp, with a low-nitrogen, low-phosphorus, high-potassium formula (NPK ratio 1:0.5:2.8).
Root Tabs Aquarium Plant Fertilizer, 100 Tabs
The listing says the tabs release nutrients steadily over 2 to 3 months, and that each tab is 1.0 g and covers about 25 square inches. It says the tabs sink quickly and are meant to be placed one every 5 to 6 inches around plant bases or the tank perimeter in a grid, pushed 1 inch into the substrate. The note for first-time use is to start with 80 percent of the recommended dose, watch plant growth, then adjust. It also says to use less if unsure and to replace the tabs every 2 to 4 months or as needed.
The listing notes that a little white cloudiness in the water is normal and comes from slow-release trace elements such as manganese and zinc, and it says those particles are safe for fish and shrimp. This is the maker’s claim, so watch your own fish when you first use it. The listed weight is 2.4 ounces for 100 tabs. This pack suits a small or single tank.
Root Tabs Aquarium Plant Fertilizer, 200 Tabs
This is the same product with 200 tabs, according to the listing, and the bullets repeat the same formula, dose and placement advice. It suits someone with several tanks or a large planted tank, since a small betta tank uses only a few tabs at a time.
Checklist you can reuse
- Timer on, light off at night, tank out of direct sun.
- Change one setting at a time and wait about two weeks.
- Root tab for root-feeding plants only, about every 5 to 6 inches, pushed into the substrate.
- Water changes to keep nitrate down; adjust the interval by watching algae.
- Trim for the look you want and to keep open swimming room.
- Keep a log of hours, brightness and fertilizer dates.
If your fish look unwell at any point, ask a vet. See also the pages on choosing a planted aquarium light and canister filters.
FAQ
How many hours of light does a new planted tank need?
Aquarium Co-Op suggests starting at 6 to 8 hours per day, then increasing gradually to 8 to 12 hours as plants grow, and shortening it if algae becomes a problem.
How often should I change the water?
The sources used here give no fixed schedule. Wikipedia says water changes lower nitrate, which helps prevent algae, so adjust the interval by watching your tank.
Do all plants need root tabs?
No. Aquarium Co-Op says stem plants mostly feed from the water, and mosses, floating plants, anubias and java fern rarely need them.
How far apart should root tabs be?
Aquarium Co-Op says every 12 to 15 cm (5 to 6 inches), or closer in a dense tank. The product listing gives the same 5 to 6 inch spacing.
What causes algae in a planted tank?
Wikipedia says algae is most often caused by excess nutrients and waste. Balancing light, nutrients and plant growth, plus regular water changes, is how the article suggests controlling it.
Bottom line
Care for a planted aquarium with a steady routine: timer light, a log, one change at a time, root tabs only where plants need them, and water changes to hold algae back.
