Tips:
-Don’t plan on your first pump being your last one. A healthy aquarium will require more flow as it matures so you will need to change pumps over time.

- Don’t use your return pump as a circulation pump. Use it to move your water through the sump but keep the flow accurate. A return pump should should move the sump water back to the aquarium not to exceed 20 times per hour. If the sump is a refugium it should be slower.

- Understand the difference between flow and intensity. You can have great intensity pushing 50 gallons per hour out of a 1/2″ pipe than 500 gallons per hour through a 2″ pipe. Most SPS need lots of flow but intensity will hurt them.

- Always use the manufactures recommended plumbing size for pumps.

- Understand that the intensity drops by 2/3 with every additional return you plumb at the same size as the original (using the manufactures recommended plumbing size)

      All clams require a stable alkalinity at 10-12 dkh. Calcium needs to be maintained at 380 ppm or greater to ensure consistent growth. Contrary to popular belief Tropics has found that aquariums that tend to be under skimmed, ususally with higher nitrates 30-50ppm tend to produce bigger, healthier clams. Clams are not as sensitive to temperature as many other corals and inverts; a stable temperature of 78 degrees is fine.  It is very important to maintain alkalinity with clams. If calcium gets to low it will reduce growth and in the long term will cause shell deterioration. If the alkalinity falls into the low 6 range, clams will die without warning. Tropics refers to clams as canaries in the coal mine when it comes to alkalinity in the aquarium. 

     Special care note: when clams are less then 2.5″ front to back it is vital to feed them. What you choose to feed is not as important as the feeding itself. Cyclops, baby brine shrimp, phytoplanton, oyster eggs, are all exceptable food choices. When clams are small they rely on the nutrients they get from the water column. The home aquarium does not have enough water rich in nutrients to support the smaller clams; this is why they need to fed at least three times a week. When clams hit about the 2.5″ size they are able to do without  the constant feeding.  At that point they use light more than nutrients for growth and health.

Tropics recommends UV sterilizers for all aquariums including reef aquariums. The concerns mentioned previously are valid but one must understand the full implication of the argument to make a proper cost vs. benefit analysis. Tropics has run many SPS, LPS, Leather, Zoanthid, Clam and mixed reef aquariums over the years all with UV. The only corals that seem to suffer a slow down on growth rate with UV are Goniaporas, Gorgonians, and clams smaller than 1.5″. Supplemental feedings would be required to ensure proper growth and health.  The home aquarium is too small to produce enough beneficial phytoplankton to keep these species well fed; clams will literally filter the aquarium water removing the phytoplankton. This means that with a few small clams you may be creating an environment that resembles what you would have while using a UV sterilizer, but you would not have any of the benefits of using UV. If you are currently supplementing your aquarium with any type of “coral food” then you should be using a UV sterilizer as you are already compensating for doing so by adding the supplement.

In Conclusion: If you choose to take on any of these species you will need to supplement the aquarium with a “coral food.”  The aquarium cannot supply enough phytoplankton for these species with or without UV. Corals, just like fish, can benefit from an environment where bacteria and parasites are not able to reach plague-like proportions, and while we refer to a few corals that may be affected, the mass quantity of coral would not have any detrimental effects from UV.