The pH must remain above 8 during the hatching process in order to ensure optimal functioning ofthe hatching enzyme. If needed (e.g. when low salinity water is used), it is necessary to increase the buffer capacity of the water by adding up to 1 g NaHCO3/L. Increased buffer capacities can also become essential when high densities of cysts are hatched (= high CO2 production). Strong illumination (~2000 lux at the water surface) is important, at least during the first hours after complete hydration, in order to trigger the start of embryonic development. Although this level ofillumination is mostly attained in daytime in transparent tanks that are set up outdoors in the shade, it is advisable to keep the hatching tanks indoors and to provide artificial illumination, in order to ensure good control over the hatching conditions. Cyst density interferes adversely with the other hatching parameters, i.e. pH, oxygen and illumination. The density may be as high as 5 g/L for small volumes ( <20 L) but should be decreased to a maximum of 2 g/L for larger volumes, to minimise mechanical injury of the nauplii and to avoid suboptimal water conditions. High cyst densities can only be maintained when pure oxygen is used, even in large hatching tanks, for example 10 kg cysts in 1 m3 tanks.
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Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.