reptileguy2727
05-05-2008, 8:30 AM
Sand as a substrate has many advantages over gravel. Sand is more natural, easier to clean, and looks much better.
Almost all the fish we keep in aquariums are from waters that naturally have a flow much lower than would have gravel as a substrate. Most will have a substrate of sand, some even silt (which we can’t really have in an aquarium). Many fish like to sift through the substrate looking for food. This behavior is allowed for much better with sand instead of gravel. In addition, many fish like to dig pits. Sand is more natural for these species, as well as easier for them to do this. The piles and slopes they create with a smaller sized substrate are not as steep as they would be if they have a larger substrate such as gravel.
Sand is also much cleaner than gravel. There is much more space between pieces of gravel, enough to allow debris in. The debris can buildup, which in time can breakdown into nitrates causing big nitrate problems. The space between sand grains is not enough for debris to get in. This keeps the debris on top. If there is enough flow in the tank the debris will keep moving until it is collected by the filters. This means less cleaning and a cleaner tank. I never have to vacuum because there is simply nothing to vacuum.
Many have a concern with pockets of anoxic bacteria developing, which can give off toxic hydrogen sulfide gas. I have not found this to be an issue. In saltwater aquariums one filtration method is a plenum. This is when there is an open area under three to four inches of sand. Even under these conditions it is beneficial anaerobic denitrifying bacteria that develop, not the harmful anoxic bacteria. I have not heard of the development of anoxic bacteria ever happening in freshwater. I would be surprised if it has not ever happened, but it seems like it is much more rare than many make it out to be. The closest thing to it in freshwater I know of is under feeding bowls that I have used in a couple of my tanks. I used wide, flat reptile feeding dishes as food bowls in a few of my tanks. When they were removed the bottom side smelled like burnt eggs (hydrogen sulfide). There were no bubbles and it was not black (which is what happens when these pockets develop). But I think this was the beginning of what could have been the development of these anoxic bacteria pockets. So wide flat areas that block off sand from interacting with the water column can cause this. This would not only include bowls, but a much more common addition to aquariums, the slate that a lot of driftwood is mounted on. This will block off all the sand below them from getting oxygen from the water column. If food bowls are used they should simply be moved weekly during water changes from one spot to another (two or three spots to rotate the bowl between should be fine). This allows the areas to interact with the water column enough to prevent the anoxic bacteria from developing.
I use Estes’ Marine Sand. It does not affect pH, hardness, or any other chemistry in any way. It also does not need to be cleaned at all. It comes in an assortment of colors. I usually use a half and half mix of black and white. This provides a not too dark, not too light substrate that is very natural looking. It costs about as much as gravel so there is not really an issue of cost when used as an alternative to gravel. I personally see no point in buying a fifty-pound bag of sand from the hardware store for three bucks just so I can spend forever cleaning it just to give up and put it in and wait for it to settle out of the water column. There are other aquarium sands appropriate for freshwater. I am not sure which are as good as, worse than, or better than Estes’, I just know I have no issues with Estes’ at all.
For certain tanks where a high pH and hard water are appropriate, many true marine sands (calcium carbonate) may be a good option. This includes hard water species like goldfish, rift lake cichlids, and snails.
Sand use with filters is a concern with many people. Estes’ Marine Sand is relatively heavy and falls very quickly when fish have a mouthful and swim off with it, slowly dumping it along the way. It drops very quickly. The fish would literally have to spit it in to the filter intakes for there to be an issue. To be extra safe all filter intakes are at least half way up the tank.
Obviously, what looks best is a personal preference. I find sand to look much better than gravel. Tanks that I have seen that have sand as a substrate seem to be more natural and look better overall. I have seen tanks that were very natural otherwise, but the gravel used (although it was average size and natural color) was actually noticeably unnatural, which can be distracting.
Almost all the fish we keep in aquariums are from waters that naturally have a flow much lower than would have gravel as a substrate. Most will have a substrate of sand, some even silt (which we can’t really have in an aquarium). Many fish like to sift through the substrate looking for food. This behavior is allowed for much better with sand instead of gravel. In addition, many fish like to dig pits. Sand is more natural for these species, as well as easier for them to do this. The piles and slopes they create with a smaller sized substrate are not as steep as they would be if they have a larger substrate such as gravel.
Sand is also much cleaner than gravel. There is much more space between pieces of gravel, enough to allow debris in. The debris can buildup, which in time can breakdown into nitrates causing big nitrate problems. The space between sand grains is not enough for debris to get in. This keeps the debris on top. If there is enough flow in the tank the debris will keep moving until it is collected by the filters. This means less cleaning and a cleaner tank. I never have to vacuum because there is simply nothing to vacuum.
Many have a concern with pockets of anoxic bacteria developing, which can give off toxic hydrogen sulfide gas. I have not found this to be an issue. In saltwater aquariums one filtration method is a plenum. This is when there is an open area under three to four inches of sand. Even under these conditions it is beneficial anaerobic denitrifying bacteria that develop, not the harmful anoxic bacteria. I have not heard of the development of anoxic bacteria ever happening in freshwater. I would be surprised if it has not ever happened, but it seems like it is much more rare than many make it out to be. The closest thing to it in freshwater I know of is under feeding bowls that I have used in a couple of my tanks. I used wide, flat reptile feeding dishes as food bowls in a few of my tanks. When they were removed the bottom side smelled like burnt eggs (hydrogen sulfide). There were no bubbles and it was not black (which is what happens when these pockets develop). But I think this was the beginning of what could have been the development of these anoxic bacteria pockets. So wide flat areas that block off sand from interacting with the water column can cause this. This would not only include bowls, but a much more common addition to aquariums, the slate that a lot of driftwood is mounted on. This will block off all the sand below them from getting oxygen from the water column. If food bowls are used they should simply be moved weekly during water changes from one spot to another (two or three spots to rotate the bowl between should be fine). This allows the areas to interact with the water column enough to prevent the anoxic bacteria from developing.
I use Estes’ Marine Sand. It does not affect pH, hardness, or any other chemistry in any way. It also does not need to be cleaned at all. It comes in an assortment of colors. I usually use a half and half mix of black and white. This provides a not too dark, not too light substrate that is very natural looking. It costs about as much as gravel so there is not really an issue of cost when used as an alternative to gravel. I personally see no point in buying a fifty-pound bag of sand from the hardware store for three bucks just so I can spend forever cleaning it just to give up and put it in and wait for it to settle out of the water column. There are other aquarium sands appropriate for freshwater. I am not sure which are as good as, worse than, or better than Estes’, I just know I have no issues with Estes’ at all.
For certain tanks where a high pH and hard water are appropriate, many true marine sands (calcium carbonate) may be a good option. This includes hard water species like goldfish, rift lake cichlids, and snails.
Sand use with filters is a concern with many people. Estes’ Marine Sand is relatively heavy and falls very quickly when fish have a mouthful and swim off with it, slowly dumping it along the way. It drops very quickly. The fish would literally have to spit it in to the filter intakes for there to be an issue. To be extra safe all filter intakes are at least half way up the tank.
Obviously, what looks best is a personal preference. I find sand to look much better than gravel. Tanks that I have seen that have sand as a substrate seem to be more natural and look better overall. I have seen tanks that were very natural otherwise, but the gravel used (although it was average size and natural color) was actually noticeably unnatural, which can be distracting.