Then, it switches off until it needs to start heating things again. The problem is that the heater will do its job and heat the water around it. Even if you place the heater in the middle, there is still a risk of cold spots happening in the absence of aeration.
That will prevent cold spots, which can occur in rectangular aquariums with a heater at one end. Water CirculationĪnother benefit of a powerhead is that it will circulate the water and distribute the heated waters throughout the tank. Bear in mind that some fish, such as Gouramis, will often breathe air from the surface naturally. If you notice your fish gasping at the surface, the dissolved oxygen has dropped to dangerous conditions, requiring immediate action on your part. Low levels will stress them and leave them vulnerable to parasites and disease. Most fish require a concentration between 5-6 parts per million (ppm) to thrive. Likewise, warmer temperatures will have a lower concentration, as will higher salinity levels. For example, your tank will have less dissolved oxygen available in higher latitudes. The concentration is a factor of atmospheric pressure, water temperature, and salinity. Dissolved Oxygenĭissolved oxygen provides a pathway for fish to breathe through their gills. A higher pH will also lower the solubility of heavy metals, many of which are toxic to aquatic life. Just set up your powerhead and let Nature take its course. Surface agitation can raise the pH to the fish’s preferred range without much work on your part. For example, African cichlids fare best in alkaline conditions, whereas Goldfish prefer a lower pH. High concentrations can lower the pH of the water and create a stressful environment for your fish.