问题：I recently did a 25-percent water change in my reef aquarium, and later that same day a film of green algae appeared on the glass. I cleaned it off with an algae magnet only to have it reappear just a few hours later. That was about a week ago. The algae film seems to be getting a little lighter every day, but I’m still having to clean up algae. Have you ever heard of this happening? What could be the cause?
-Personal communication from fellow hobbyist
答案：我不仅听说过这种情况，而且我在多年以上作为业余爱好者的多年来也经历了它。您正在遇到的花朵的广泛解释是，您的水变化程序的某些方面是引入或解放耗尽藻类的溶解营养素。考虑到水的全部变化，这似乎是违反直觉的，它是用没有的水代替含有溶解的营养素/污染物的水，但可以以各种方式发生。让我们探索更常见的：
First, what type of source water are you using when you mix up a batch of salt water? Are you using plain dechlorinated tap water or are you first purifying the water, e.g. through a reverse-osmosis/deionization (RO/DI) system? If you’re simply using dechlorinated tap water, that could very well be your answer right there. Tap water can contain a wide variety of nutrients and contaminants that may be deemed safe for people to drink (arguably) but aren’t ideal for reef systems. If, for example, your municipal water supply contains nitrate and/or phosphate, you’re essentially fertilizing algae with each water change and freshwater top-off. A good RO/DI system will remove the vast majority of impurities and, thereby, eliminate a lot of guesswork.
如果您已经在使用RO/DI净化源水，还需要确保系统正在尽其所能。确实需要在制造商示出的间隔（或更频繁地取决于诸如使用水平和源水的质量）以保持峰值性能。廉价的TD（总溶解固体）仪表将帮助您确定产品水中的污染物水平是否上升到不可接受的水平。
Another factor to consider is the salt mix itself. Quality synthetic salt mixes are nitrate- and phosphate-free, but not all salt mixes are created equal in this regard. If you’re using RO/DI water from a quality, well-maintained system and testing indicates the presence of nitrate and/or phosphate in your salt water before it’s added to the tank, there’s a good chance the salt mix is introducing these nutrients.
您的水族馆底物（如果有的话）是要考虑的另一个因素。干扰底物，例如搅拌或真空时，可以将被困的养分释放到水柱中，从而加剧藻类的生长。我个人在具有较大颗粒大小的底物的系统中观察到了这个问题，该系统可能会捕获大量的碎屑，以及具有较细的底物的系统，该系统不足以促进硝化。
最后但并非勒ast, check out your sump (again, if you have one) to make sure it’s clean. Being the lowest point in the aquarium system, sumps can collect a lot of detritus over time, especially if they’re situated out of sight and out of mind. Then, if you stir up the detritus during a water change—for instance when removing a component for cleaning—a lot of that nutrient-rich gunk can cloud the water and get pumped right into the display tank when you power everything back up, thus fueling an algal bloom.
好消息是，一旦引发加油的引入/解放的营养素，盛开应最终消退。尽管如此，您仍需要确定问题的根源并进行补救，因此每次换水时都不会重复这种情况。
