Getting to the Bottom of Aquarium Sand and other Substrates

选择盐水水族馆的底物（放置在储罐底部的材料）是我们爱好引起混乱和分歧的许多领域之一。询问10个爱好者，他们会推荐哪种类型和深度，您可能会得到10个不同的答案。事实是，在所有情况下，都没有适合每个系统的单个底物粒度或深度。

让我们深入研究这个主题，以便您可以根据自己的目标为系统选择合适的底物。

底物做什么？

底物所做的不仅仅是躺在那里看起来很漂亮。除了创建一个漂亮的海洋美学外，底物还可以执行许多重要的功能。他们之中：

• Providing biofiltration by supporting colonies of the beneficial aerobic bacteria that convert ammonia to less toxic compounds
• Providing a suitable home for various beneficial microfauna, such asamphipods，，，，copepods，，，，tiny brittle stars, etc.
• 提供适当的条件，用于挖洞，埋葬和散落的物种，例如颚鱼，各种wrass，某些吞噬物，Cerithium spp.snails, etc.
• If depth and grain size are appropriate (at least 4 inches of fine sand), supporting colonies of anaerobic bacteria that convert nitrate to harmless free nitrogen gas

保持钙质！

Forget the colored quartz gravels widely used by freshwater aquarium hobbyists. Ideally, the substrate medium you choose should be calcareous, or composed of calcium carbonate. Some common types include aragonite, crushed coral or coral sand, and crushed seashells of various grain sizes. Aragonite is one of the better choices because it dissolves at a relatively high pH, which means it will do a good job of buffering thepH of the water在适合海洋牲畜的水平上。

我应该使用什么晶粒尺寸？

同样，这里的答案取决于您的牲畜和过滤目标。例如，如果您打算通过吸收底物并将其通过ill驱除的鱼来饲养一条鱼，例如Valenciennea spp.sleeper gobies, a very fine-grained, smooth-edged (e.g., oolitic) sand would be appropriate. Burrowing species, such as the yellowhead jawfish, need a substrate of mixed particle sizes, including rubble, to construct a sturdy burrow. If you plan to install a deep sand bed (DSB) for the purpose of natural nitrate reduction, very fine sand is the medium of choice.

On the other hand, if you aren’t keeping burrowing or sand-sifting species, you aren’t interested in natural nitrate reduction with a DSB, and your only concern is having an aesthetically pleasing substrate, the grain size is really up to you. Just keep in mind that the larger the grain size of your substrate medium, the more it will tend to trap detritus in the voids between particles, which necessitates regular vacuuming.

How deep is deep enough?

If you plan to incorporate a DSB in your setup and/or to keep burrowing/sand-sifting species, a minimum substrate depth of four inches is recommended. Otherwise, a depth of just a few inches is more than adequate to give your aquarium a nice natural look and provide the right environment for aerobic nitrifying bacteria to flourish.

信不信由你，有些业余爱好者选择将其底部完全暴露出来 - 他们的坦克底部。与所谓的底部（BB）坦克，您不必担心底物捕获颗粒物废物并成为持续溶解污染物的来源。但是，权衡是它们并不是自然的。