Once your saltwater aquarium has fully cycled, it is vitally important to setup a maintenance schedule and routine to help maintain a stable environment within your tank.

Regular maintenance includes water changes, water testing, algae scrubbing and dosing additives and/or supplements. In this article, you will learn how often to perform these maintenance chores for a saltwater/reef aquarium and get tips and product recommendations to help you along the way.

Let’s begin with a list of common items used for normal aquarium maintenance (such as a water change). There may be some items here you don’t need, but generally speaking, these are the tools most hobbyists use to maintain their aquariums:

  1. Siphon tubing with gravel cleaner (Python, Hagen and Eheim)
  2. Algae magnet (great for every day cleaning; leave right in the tank!)
  3. Algae pad (for reaching areas the algae magnet can't)
  4. Algae scraper (cuts right through hard algae growths, like coralline algae; a must have tool for your tank)
  5. Gloves (to protect yourself and your tank from contamination)
  6. Aquarium polish (used on the outside of the tank after you are done with your maintenance to get rid of water spots and fingerprints)
  7. Water containers (5-gallon buckets or Tote garbage cans for both pre-mixing saltwater and siphoning tank water into)
  8. Heaterthermometer and powerhead for making up saltwater for your water changes
  9. Towels (don’t use the good bath towels!)
  10. Aquarium Journal (record your maintenance schedule so you keep on track)

Water Changes: Out with the old (saltwater), in with the new (saltwater)

Almost everyone knows and agrees that water changes are needed in all aquariums, but the actual amount or percentage of water to change and how often to change the water is a subject that is more debatable. You will hear people recommend numbers like “10% of your water once per week” to changing “50% once per month” and everything in between. In reality, there really is no right or wrong answer. For many people, weekly water changes work for their tank while for others, the larger once per month water changes work best for their tank. I personally prefer to change about 20% of the aquarium water every 1-2 weeks. Basically it boils down to finding what works best for both your schedule and your tank’s overall health.

TIP: For a saltwater aquarium, you will need to mix the new saltwater at least one day prior to performing your water change. This will allow you to match the salt and temperature levels of the new saltwater with the water inside your aquarium. A 5-gallon or larger bucket/container with a powerhead and heater work great for pre-mixing saltwater.

Where to begin?

I start by scrubbing the algae on the glass of the tank with an algae magnet, algae pad and/or algae scraper. This will loosen the algae, making it easier to siphon out once you start removing water from the tank. After you’ve given the algae a chance to settle, you are ready to begin siphoning water out of the aquarium.

TIP: Before you start siphoning water from your aquarium, be sure to unplug any electrical items that may be affected by the drop in water level. This will prevent your heaters, powerheads, return pumps, filters or auto top-off systems from sustaining damage while running dry. Cleaning with your aquarium lights off helps to reduce any undue stress to your aquarium’s inhabitants.

With your algae now scrapped clean, your electrical devices unplugged and your new saltwater water pre-mixed, it is time to siphon water out of the tank. Using a siphon with a gravel cleaner comes in handy because it allows you to pull detritus out of the gravel without siphoning out the gravel itself. Siphon the water into an empty bucket or container so you can match the amount you remove with the amount you have prepared to replace it with.

TIP: Most people use sand in marine tanks, which can be problematic for a gravel cleaner since sand is light enough to be pulled out with the detritus. What I suggest to people with a sand bottom aquarium is to either pinch the vinyl siphon tube to slow down the flow (allowing the lighter detritus to siphon out, while the sand stays in the tank) or mix the sand up a little bit before siphoning and then just siphon towards the top of the sand.

At this point, you should have an aquarium that is 10-50% drained, ready for new saltwater to be added. There are a few ways to go about adding the new water to your tank. For smaller tanks where a bucket is used to mix the saltwater, you can just slowly dump the new water in. For larger tanks where lots of water will be required, I find using a large powerhead (a Mag-Drive pump, for instance) hooked to flexible tubing to pump water back into the tank works extremely well and saves your back from unnecessary strain.

TIP: Don’t add water back into your aquarium too quickly: you don’t want to knock over your tank décor, corals or stir up the sand bed.

You have now completed your water change. Double-check to make sure the water level is correct (i.e. you have added back the same amount you siphoned out). If the levels are correct, you can start plugging back in the electrical devices you had previously unplugged, making certain they are all running properly.

There’s just one more task to complete before you can sit back, relax and enjoy the tank (besides cleaning up after yourself): get out the aquarium polish (do not use window cleaners on a fish tank, inside or out, as they are harmful to the tank) and wipe down the glass or acrylic to get rid of any water spots or fingerprints. You will be amazed at how much water spots, fingerprints and even dust obstruct the beauty of your tank. Just a minute or two of wiping down your aquarium will go a long way.

Besides water changes, what else may need to be done?

Water changes are no doubt one of the most important things you can do to maintain a healthy aquarium. Still, there are other chores that should be completed on a (fairly) regular basis. The following duties (and estimates of when to do them) should be incorporated into your regular maintenance routine:

  1. Water testing
    1. Salt levels: test daily (use a refractometer or hydrometer)
    2. pH: test daily or weekly (use test kits or monitors)
    3. Ammonia and Nitrite: test monthly (use test kits)
    4. Nitrate and Phosphate: test weekly (use test kits)
    5. Alkalinity, Calcium and Magnesium (reef tanks): test weekly (test kits)
  2. Cleaning pumps (powerheads, return pumps, protein skimmer pumps, etc.)
    Once per month to every other month. Some pumps may be able to go longer, but do not put this off until the pump stops working. Keep on top of cleaning them to help extend the life of the pumps. If you are getting a lot of calcium build-up on the impeller or other parts you can soak them in a vinegar solution. If the calcium build-up is heavy you can use straight vinegar, if it is lighter build-up usually a 50/50 diluted solution with RO water will be fine. Usually around a 5-15 minute soak works well. Rinse them thoroughly afterwards with fresh or saltwater.
  3. Cleaning your protein skimmer
    Daily to weekly cleanings (sometimes monthly, depending on skimmer type). Skimmers need to be kept clean in order to function properly. Draining the skimmate and cleaning the inside of the skimmer should be part of your regular maintenance.
  4. Overview of your tank
    Daily. This is overlooked by many hobbyists but is very important. You should look over your tank and its equipment every day to make sure everything is running properly. Get to know the behavior of your fish and invertebrates so you’ll notice when they aren’t acting normal; get to know the sounds of your tank so you can hear when something is not running properly and visually inspect your heaters, thermometer, monitors, etc. daily to make sure they are all running. A quick 5-10 minute overview of the tank once per day can prevent major disasters from occurring.
  5. Feeding
    Daily. I am not sure if feeding is considered a maintenance task, but I did want to mention it because it is a good time to look closely at the inhabitants in your tank. Feed a variety of foods to your fish including flakes, pellets and frozen foods.
  6. Additives/supplements
    Daily to weekly. Fish, corals and invertebrates will utilize minerals and nutrients directly from the water. The use of additives and supplements will help replenish your aquarium water for your tank inhabitants to use.
  7. Changing your light bulbs (especially reef tanks)
    Every 9-12 months. Corals rely on the artificial light you provide for them. The bulbs slowly degrade over time and need to be changed out. Metal halideT5 fluorescent and VHO fluorescent bulbs should be changed about once per year. Power Compact (PC) bulbs should be changed out about every 9-12 months.
  8. Filter media (carbon, phosphate removers, etc.)
    Weekly to monthly. Most carbon and ferric oxide-based phosphate remover medias will last about a months time and should be changed out according the manufacturers recommendations.


If you want to have a successful aquarium, regular maintenance must be a part of your routine. Keeping up on the basic maintenance of your tank will pay off with a healthy tank that can be the envy of other hobbyists. While initially it may take you several hours to perform even the easiest of tasks, as you progress in the hobby and gain experience, you will find it takes less and less time to to get everything done … giving you more time to enjoy the tank.