reef aquarium maintenance

A Simple Reef Aquarium Maintenance Schedule

A Simple Reef Aquarium Maintenance Schedule

Many aquarists view themselves as stewards of the marine life in their aquariums. Not only is it fun building a reef, we feel a responsibility to properly care for the fish, corals and other invertebrates that live in our home. Proper care means having a plan to maintain the aquarium health, and the best way to do that is with a simple reef aquarium maintenance schedule. You’ve heard the old saying Failing to Plan is Planning to Fail. It’s no different with our aquariums. I’ve outlined a basic maintenance schedule that takes you through a new marine tank start-up, all the way to managing a mature reef aquarium.

reef aquarium maintenance

From wikihow

It all starts with testing the water

Some people love testing aquarium water, others hate it. Either way, you gotta do it. To make sure that I do it, I like to consider the testing as part of my reef aquarium maintenance schedule–that way I don’t give myself permission to slack on it. Keeping an eye on water quality will prevent many problems before they cause significant trouble in the reef tank.

 pH and Alkalinity: Once a week

pH and alkalinity go hand in hand. The pH is stabilized by the carbonate buffers dissolved in the saltwater. Alkalinity is the measure of these carbonates. Saltwater mixes are formulated with adequate buffering to set the pH around 8.2 to 8.4. Natural processes in the tank produce acids that neutralize and use up the buffers. As corals and other encrusting marine life build their calcium carbonate skeletons, carbonates will be removed from the water and alkalinity will decline. As alkalinity levels drop you will eventually see the pH start to go down too. What to do about it? Wait until we talk about calcium levels.

 Calcium: Once a week

If you are building a reef aquarium you want corals to thrive and grow. Growing means they are removing calcium and carbonate (alkalinity) from the water and creating a coral skeleton. Encrusting coralline algae will also use calcium and carbonate. Calcium is measured with a calcium test kit. Calcium is tied to alkalinity. Both will drop over time. I suggest testing pH, alkalinity, and calcium once a week for the first month or so. Write down the levels so you can see trends over time. You will see that alkalinity fluctuates up and down, while calcium is relatively stable. This is normal. Watch for a trend where alkalinity is consistently declining. Then, replenish alkalinity (and calcium) with a balanced calcium and alkalinity additive. Some aquarists buy a two-part product, some use lime water and the hardcore reefers buy a calcium reactor. In all cases, the balanced replenishment of calcium and alkalinity will stabilize pH, alkalinity and the calcium level. After a couple of months, you can reduce the testing to once a month. By this time you will know the rate of change in your tank and know-how often tests should be made.

 Ammonia and nitrite: Once a week

When starting up a new tank it is essential, and educational, to track the rise and fall of ammonia and nitrite during the establishment of the biological filter. This classic “cycling” period can take about 30 days. Monitoring ammonia and nitrite during this phase often frustrates new aquarists. Sometimes the levels seem to go unchanged for days. Then, finally! Ammonia and nitrite fall to zero. Once the biological filter has become fully active, testing ammonia and nitrite can be reduced to once a month. There is no reason to expect these levels to rise again unless something goes wrong in the tank. If a fish or invert dies or goes missing, it is wise to begin testing to make sure water quality is OK.

 Nitrate: Once every two weeks

Nitrate is the end product of biological filtration. Ammonia is converted to nitrite, then to nitrate. As the biological filter starts up in your new aquarium, you’ll see nitrate gradually climb. This makes sense since a rise in nitrate shows the biofilter is working. Once your tank has cycled through, a water change is recommended to reduce the nitrate level. Nearly all reef keepers agree that keeping nitrate as low as possible is desirable. Many reef tanks begin to remove nitrate naturally as they mature, through biological denitrification. If you’ve got a nano reef, a small water change once a week is easy and will help keep nitrate levels low. Once your reef has been set up for a few months, you may only need to test nitrate once a month.

 Phosphate: Once a month

Phosphorus is both an essential element and a nuisance. All living things require phosphorous to survive. It is also a waste product of metabolism, released into the aquarium from plants and animals. We measure phosphorous with a phosphate test kit. Phosphate is not toxic but it can interfere with coral growth by inhibiting the formation of the calcium skeleton. Excess phosphate can also stimulate algae growth. Test phosphate once a month. Make water changes or use a phosphate-removing media to keep it under control.

 Filter Maintenance-Yuk!

reef tank maintenance

image from wikipedia


I’ll be honest. I like cleaning my aquarium filter. I mean I like getting rid of dirty cartridges, clogged sponges and slimy old chemical media. But I don’t like the mess I sometimes make in the sink or on the floor. This is precisely the reason so many of us put off filter changes. Eventually our canister clog, our sumps become sludge pits, protein skimmers are overflowing with gunk and our water quality suffers. Here is the remedy. If you have one, clean the filter once a month! Check and clean the skimmer too. It is probably easiest if you clean the skimmer each time you empty the skimmate cup, but if you don’t make sure to do a more thorough cleaning about once a month. Put it on your calendar. Set it as a recurring event on your computer and your phone! Just do it. You’ll love how your fish and inverts perk up when the filter is clean and the skimmer is working properly.

 Water Changes-Why and When?

Changing water dilutes the natural organic compounds that build up in our aquariums. Unlike the natural reefs, we don’t have tides that flush everything out for us. Water changes also replenish trace elements that are used up by algae and inverts. Water changes can dilute excess nutrients, like phosphate and nitrate, which stimulate algae growth. Many aquarists like to make a water change every two weeks. Some argue for frequent small water changes while others go for larger amounts, around 20% of the tank volume. The choice is yours. Out with the old, in with the clean new seawater!

 A Clean Reef Tank is a Happy Reef Tank

reef tank maintenance

image by Dieter_Karner

My aquariums always look better when I keep up with this simple reef aquarium maintenance schedule. I find I am more in tune with what is happening in my reef too. I notice corals budding. I pluck out a tuft of algae before it takes over. Sticking to a maintenance schedule actually reduces work. You won’t experience those ‘Wow! My tank looks terrible!” emergency clean-up sessions. So get busy and start enjoying your reef tank more!

If you’re like me, you may have some issues staying motivated and on-schedule. A great way to help stay on schedule is to use Google Calendar. Check out how I use it in my aquarium maintenance productivity hack article.

To dive deeper, check this out:

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