SPS corals are also called Small Polyped Stony corals. These are different than LPS, which are also called Large Polyped Stony corals. Both SPS corals and LPS corals are reef building corals and each polyp will build a stony skeleton, while soft corals don't usually leave a stony skeleton behind when they die.

When you go to the shops in Florida that sell coral skeletons, you can see SPS and LPS coral skeletons. The skeletons are made up of primarily calcium carbonate (CaCO3) , but they also have other many other major and minor elements and compounds.

Much has been written about popular SPS corals and we really can't tell you everything about them here. Entire books have been written on SPS corals, but we do want to cover some important considerations for beginners.

However we do recommend that you get your feet wet with soft corals and fish before you tackle keeping SPS corals. That's why, for now, we wont go into too much detail on SPS corals.

Water Requirements

SPS corals require different water parameters than soft corals do, for their survival, and especially for their maximum growth. They prefer to have close to zero measureable Nitrates, because these Nitrates can inhibit the building of their skeleton. in other words, the calcification of their skeleton can be slowed or stopped by higher levels of Nitrates in the system. So it's very important that both nitrates and phosphates be zero or as close to zero as possible.

Strong current and excellent intense lighting of the proper spectrum are very important in maintaining healthy colorful SPS corals.

Building their Stoney Skeleton

Because their skeleton is build out of compounds that are dissolved in the saltwater, it is important to replenish these compounds constantly. This can be done using a calcium reactor, or a two part solution, or even a kalkwasser drip.

Keeping SPS and Softs together

It is possible to keep SPS corals in the same tank as soft corals. But the tank will not be optimal for either group. Either one or the other will benefit to the exclusion of the other. Often you can find a healthy system where you have stony corals and soft corals happily growing together. If they're both doing fairly well then, such a system would be sort of an average between the two extremes or parameters and neither the soft nor the SPS corals would really be getting the proper conditions for them to grow to their maximum potential. So you can mix softs and SPS, but neither will be in optimal conditions.

In the ocean, you don't really see a lot of mixing of the two types of corals soft in SPS except in sort of micro environments. You have regions on on the reef where the stony corals dominate and then you have regions on a reef where the soft corals dominate and these have grown there naturally because of the prevailing favorable conditions.

For information on the optimum SPS conditions, visit our section on SPS Parameters [link to SCI

SPS corals are considered to be the ultimate challenge in keeping corals. They are certainly the most difficult types of coral to keep. But by doing a few things right within your system. It's really not that difficult to keep them.

SPS from Coral Farms

If you can start out using SPS corals from one of the coral farms, you will have several advantages. If you buy from a coral farm, then at least you know that these grow well in captivity. There are many types of SPS coral that you can get from the wild that are very difficult if not impossible to keep alive. And those will still be offered for sale. But if a farm is growing sufficient amount of SPS corals to sell them, then obviously they're able to do well in captivity.

If you do buy a SPS coral from a farm, be sure to find out what conditions they grow them under so you can use that as a guide for your tank. Any reputable coral farm should release that information so that you can maintain your corals in the healthiest environment.

Once you've started collecting SPS corals, you might find yourself needing to trim them before they outgrow your tanks. Be sure to visit our section on coral propagation to find out how to do that.