How to Set up a Small Reef Aquarium

This is a guide to setting up small reef tanks. It will guide the reader from initial set up to a completely cycled tank. This tank setup can run successfully for over 5 years.


  1. Image titled Set up a Small Reef Aquarium Step 1
    Acquire an aquarium. This guide is for tanks less than 30 gallons (113.6 L). Decide on the location of the aquarium in your home. This place should have lots of circulation and have zero exposure to direct sunlight. Tanks of this size can be placed on a sturdy piece of furniture. You can also purchase a pre-manufactured stand which may increase the warranty on an aquarium. Also be sure to get the items in the "Things You'll Need" section.
  2. Image titled Set up a Small Reef Aquarium Step 2
    Fill the tank with water. Always Use R.O.D.I. water. Tap water will not work and will lead to massive algae break outs as most tap water has many phosphates and silicates. If you do not have an R.O. unit, buying premixed water from a reputable local fish store is a great option. You may also experiment with distilled water from the store however if the water has copper in it (distilled in copper containers), it will kill coral. Be sure to leave about two to four inches at the top of the tank.
  3. Image titled Set up a Small Reef Aquarium Step 3
    Add salt in small amount while checking with the hydrometer into a container other than the aquarium. Continue adding salt and stirring and checking salinity until the hydrometer reads somewhere between 1.022-1.025. With a new hydrometer you will frequently get air bubbles stuck to the needle, these will seriously throw off a reading. Tap it up and down and left and right until they float off. Once you have an appropriate salinity take a break and let the water clear up. Pour the water into the aquarium. Check it again and proceed to the next step.
  4. Image titled Set up a Small Reef Aquarium Step 4
    Put the entire unopened bag of sand into the water. Slice open one side of the bag and slide it out very gently. It is similar to the magician pulling out the tablecloth, but a lot slower. If you do this properly the tank will hardly cloud at all. If you don't, you will have to wait longer for the water to clear so you can see through the aquarium. (You may use sand bought at the pet store or live sand bought from a local reef store)
  5. Image titled Set up a Small Reef Aquarium Step 5
    Test the alkalinity and calcium levels. Read the directions for the test kit they vary in methods. Alkalinity reading should be 8-12 dKH. Calcium should be at 400-500 ppm. If either tests low, add an appropriate amount of alkalinity increase or calcium increase.
  6. Image titled Set up a Small Reef Aquarium Step 6
    Place your rock in a way that is visually appealing to you. Keep in mind that you will need to clean the glass so leave enough room on any sides you will be cleaning, really important on the front pane. It is also advisable to stack the rock in an arch formation with many open holes and few touching regions.
  7. Image titled Set up a Small Reef Aquarium Step 7
    Assemble the filter. Place the filter in a place where it will maximize the flow in the aquarium. The middle works better than the sides. If you are using two filters place them on opposite sides but not on the edges. Read the directions thoroughly before you plug them in. Make sure the filters are running properly.
  8. Image titled Set up a Small Reef Aquarium Step 8
    Put on the glass top, but leave the back plastic piece that comes with it off for now. Leaving this off allows a ventilation in the tank and keeps the temperature lower.
  9. Image titled Set up a Small Reef Aquarium Step 9
    Cycle the tank with a fishless cycle additive i.e. Dr. Tim's or add a few small cheap hardy fish and wait around a month to a month or two for ammonia, nitrite, and nitrate levels to zero out and the biological filters to establish Then head over to the BRS web sight and watch as many videos as possible on running your reef.


  • A larger tank is more costly, however, it is more stable. In other words, do not start out on a five gallon tank. (I would recommend a thirty gallon tank.)
  • Do not let the L.F.S. talk you into buying damsel fish to cycle the aquarium. This technique is cruel and you will be stuck with a mean, territorial fish.
  • Along those lines, don't let the L.F.S. talk you into buying anything you don't need or want (especially if you know it is unnecessary).
  • Clean salt creep away from the aquarium to make it look presentable.
  • Coral fragments (frags) can be bought cheaper than a whole colony. They are ecologically friendly, cheaper, and if you are not sure you can take care of the coral it is better to try on a small piece.
  • Clean glass bi-weekly with a damp towel.
  • Many dry goods can be purchased through online stores cheaper than at the pet store.
  • Research! research! research! The more you know the better you will know how to deal with problems. Assuming that you have access to the internet; become a member on reef forums such as [] or [1]
  • You must have patience. Everything will be more stable if you are patient. Don't rush into the pet store and start buying things (or fish). Plan ahead, price things, don't take a blind dive.
  • Look for a reputable local fish store (L.F.S.). Some may be small hole in the wall stores or large warehouses. Either way, determine: if the livestock is healthy, if the tanks look clean, are the workers knowledgeable, are the prices reasonable, etc. etc.
  • Perform a monthly 25% water change, or several small 5% changes.
  • You don't actually have to wait a month for bio levels,and nitrate,phosphate,and all the levels to get to where there supposed to be. You can purchase a packet of bio(bacteria,and other chemicals that support your tank)and put it in your tank. If you do, test to make sure everything is going well, and add chemicals when necessary. It will only take about a week before your tank is ready for fish. It takes about a week for a 55 gallon (208.2 L) to be ready for fish, so it would probably take less time for anything less.
  • Fellow hobbyists are usually kind and will be glad to try to help you. However, keep in mind that some things on the internet have to be taken with a grain of salt (no pun intended).

Things You'll Need

  • 1 lb of live sand per gallon. Live sand is available in 10-20 pound bags, putting 20 pounds in a 10 gallon (37.9 L) tank is acceptable. This will produce a one to two inch deep sand-bed.
  • a hang on back filter that pushes 10 times your tank capacity per hour. For a ten gallon tank a filter that does 100 gph will be suitable. For 20–30 gallon (75.7–113.6 L) tanks it is frequently better to get two smaller filters as it will create better flow in the water. It is crucial that the filters have a biological element. Some have special wheels or sponges designed to be biological filters and this is the most important type of filtration in your new tank.
  • A protein skimmer may also be utilized for larger tanks (over 12 gallons). There are many styles and designs; some better than others. Protein skimmers are very efficient filters and are often the only type of mechanical filtration employed. Allow two weeks as a break-in period.
  • a power compact, T5 VHO, Strong LED, or metal halide lamp that fits your tank. This can be the most expensive single item you buy. If you come across a used one it would be desirable to replace the bulbs. Make sure any light has both Actinic and 6500 to 20k Lights
  • Salt. Salt is sold by how many gallons it makes. Get an appropriate amount.
  • A Hydrometer. This device measures the salt content of your water and is crucial for maintaining a proper salinity. Some hydrometers do not tell the salinity.
  • Some type of water detoxifies. Usually carbon and or Chemi-Pure and some sort of phosphate absorbing conditioner such as GFO or phosban.
  • A test kit is essential to the initial setup of your tank.
  • Live Rock. Your local reef supply store will have live rock on display. Select rock that looks interesting to you as you are going to be looking at this initial rock for the rest of your tanks days. try to get live rock that is 'clean' looking with a good growth of coralline algae. You don't want any unwelcome guests like brown anemones. They look nice, but they will kill more desirable tenants. Also, keep in mind that you can use a few pounds of base rock (coralline free) to create the bottom of the reef structure.
  • Reef additives. Several major manufacturers of reef supplies have products for the smaller reef tank. It is crucial that you can increase the calcium and alkalinity levels of the water.
  • For a fishes cycle you can *Add one or two frozen shrimp, Test for the ammonia to spike, once it spikes take them out and let the cycle go(4-6 weeks) After this add 2 fish per month until all fish are bought
  • Power-heads to create adequate flow. These may not be necessary depending on the flow created by the filters.
  • A heater to maintain the temperature at a steady 80 °F (27 °C).

Article Info

Categories: Aquariums