Sumps, Should I Use One?

There are various ways of improving the chances of success when designing a [tag-tec]saltwater aquarium[/tag-tec]. Using modern effective methods of filtration, correct and appropriate lighting and stocking properly are some examples.

Whatever the type of aquarium that is being considered, be it fish only or reef, using a [tag-tec]sump[/tag-tec] is always an excellent move. The sump will improve the chances of success considerably more in the reef system, but will improve matters in the fish only aquarium also. Some aquarists have no choice, they say they don’t have the space. On some occasions this is correct, but in others, may I ask, what is the aquarium standing on? The reply will be a cabinet, and more often than not a sump will go in the space below the aquarium.

Why is having a sump such a great idea? It means that the number of gallons of seawater in the aquarium is going to increase. This is excellent, as the more gallons there are the more stable the seawater chemistry is going to be. Also, it will be more difficult to upset that stability by overdosing etc. This means that the fish and corals are going to have a better environment, live a healthy life and prosper. That can’t be bad!

The [tag-tec]aquarium sump[/tag-tec] should be as big as possible. For the majority of aquarists this means a sump that is smaller than the display aquarium, as this is what can be fitted in. It may seem ‘backwards’, but there are aquarists who have a sump that is bigger than the display aquarium, the whole idea being that the water quality in the display aquarium will be superb, as the total net gallonage of the system is very much greater. A caution though. Having more gallons does not mean having more stock in the display aquarium. This would negate the advantage. The display aquarium should be stocked for its physical size and net gallonage on its own.

More seawater gallons is not the only advantage though. The display aquarium can be for the reef and fish, with necessary support equipment out of sight (excluding circulation power heads etc). The heaters and protein skimmer(s) can operate in the sump. Carbon filtration and the like can also be located in the sump, with incoming water running through it.

Further, a DSB (deep sand bed) can be located in the sump. Some aquarists place their DSB in the display aquarium. This is fine, but, in my opinion, not ideal. The thick layer of fine sand may well be blown about by water currents. There may be problems with the sand and the rock structures (cleanliness, access, compaction etc). Also, the life on and in the sand bed will be generally more open to predation by the aquarium inhabitants. Why not place a DSB in the sump where there is easy access, no compaction, and the tiny life forms can proliferate and prosper without being in danger of becoming a ready meal? True, they are predated on the reef, but the reef is somewhat larger than out aquariums! Also, a few, maybe a lot, will find their way into the display aquarium where the fish can find them. If sand is required in the display aquarium (and it does look very attractive) then a thin ½” layer will do. It is then more easy to maintain. As it has no filtration duties, it can be stirred to remove detritus and maintain its appearance. This cannot be done with a DSB (or shouldn’t be).

If a rogue is discovered in the display aquarium, and can be caught (an achievement in its own right sometimes) then, until final disposal to a shop or fellow aquarist can be arranged, there is some temporary accommodation for it.

There is no reason why a successful marine aquarium cannot be achieved without the use of a sump. However, with a sump the probability of success is considerably increased.