Aquarium sand is something that all salt water aquarists are well aware of. The question above is a simple one, but not quite as simple as it appears.
The first [tag-tec]aquarium sand[/tag-tec] that aquarists usually come across is the fairly coarse variety. This will have particles around 1 to 3mm or so. It was commonly used in the ‘old’ days with under gravel filters. Nowadays it is often used for decoration in the main display aquarium. A layer of, say, ½ to 1″ is used, and sometimes made into small dunes for effect. Now to answer the question. Yes, most definitely. It will be detrimental to the aquarium if detritus is allowed to accumulate on or in the sand.
It is a good idea to clean the sand before it is put into the aquarium. Rinse it several times in a bucket until the water runs clean. Tap water will do, but make sure it is allowed to drain away before the sand is placed into the aquarium.
Again before the sand goes into the aquarium, it is recommended to place it in a thin layer. This will need to be done in small batches. Obtain a powerful magnet and run it over the sand. Metal has been found on a few occasions in sand. Metal in the confines of an aquarium is not good news!
The sand when in place in the aquarium should be gently stirred occasionally to allow detritus to escape into the water column. Hopefully, this detritus will be carried by the currents to within reach of filter intakes. The dirt that isn’t may well settle in an area of relative calm. This should be siphoned out. The sand stirring operation can be carried out according to need. This operation shouldn’t be necessary more than, say, once a month, but this will vary with individual aquariums. If there is a tendency for the sand to lose its colour because of algae (often a very thin patchy layer on the surface) then stirring will get rid of that also. However, ensure that the sand is clean. Also, check the water parameters. How is the algae developing?
If the decorative sand in the aquarium is found to be very dirty then it can be removed by siphoning at water changes. There will be too much for one water change so the operation can be extended over several, removing one area of the sand at a time. Then clean in a bucket before replacing it.
This is fine sand with particles much smaller than the decorative variety described above. It can be blown about by power heads etc quite easily. This is the sand used in DSB’s (deep sand beds) and plenums. It is usually 4″ or more in depth and has filtration and other advantages in the aquarium. The sand can be in the main aquarium, or in a sump. (It is my opinion that the bed is better off in a sump, as it will be generally free of rockwork, be easy to observe in its entirety, be of a generally uniform thickness over its whole area, and the tiny life forms that should inhabit the sand are away from the predation dangers of the main aquarium.)
Now to answer the question. These sand beds cannot be stirred whenever as can the decorative one. If the sand bed theory has been properly studied, it is set up correctly, and it has a good population of various life forms, it is quite likely to look after itself. However, problems can arise. If the surface of the bed is becoming covered in detritus, and this detritus continues to increase, the first action is to attempt to siphon it out. This is not an easy operation as the fine sand can be sucked up very easily. The exercise should be undertaken with the utmost care and patience and every effort made to remove/disturb as little sand as possible. Also remember the siphoning action will probably remove a fair number of the little life forms, not a good thing. It is obvious that an investigation into why so much detritus is being produced should be undertaken. It must be prevented. A noticeable but small amount of detritus on the sand surface is normal. In these sand beds the sand rarely looks particularly clean at the surface. It can be observed that the normal small amount of detritus that arrives daily is not increasing, as it is being dealt with naturally. If an algae film appears on the sand surface then, using a small clean stiff stick, the sand surface can be very gently stirred, making sure that penetration into the sand is minimized. If the sand in its depth is filthy, particularly if there are blackened areas on the surface and/or can be observed through the glass sides of the aquarium or sump, the only real action is to remove the sand and begin again. This is a very serious action and should not be undertaken unless the aquarist is certain there is no alternative.
I’ll repeat, however, that if the aquarist has properly studied the theory, setting up, and maintenance of a DSB or plenum, then the probability is that there will be minimal problems.
So, looking at the question again, the answer should really be “Yes, but…..”