几种碱性试剂对循环水养殖系统中pH值调节的研究

在循环水养殖系统中pH值会因为鱼类所排放的CO2和硝化反应所产的酸而降低，过低的pH值会对鱼类生长产生十分不利的影响。因此加碱调节pH值对于维持循环水养殖的稳定运行时非常重要的。目前关于这方面的研究以理论分析为主，具体实验研究较少见。采用氢氧化钠、碳酸钠、碳酸氢钠溶液对采集于淡水循环水养殖系统中的水样进行滴定实验，得到相应的滴定曲线，与同等条件下滴定的去离子水曲线比较后发现，淡水循环水养殖系统中的水体具有缓冲性。氢氧化钠的滴定曲线与碳酸钠、碳酸氢钠的滴定曲线相比，在突越点前和在突越点后，pH值的变化都相对剧烈，为了避免加碱后会对水体pH值产生较大波动，宜选择碳酸钠、碳酸氢钠等弱碱性物质。同时，在pH值降至突越点之前，补充碱性试剂是一个较合适的时机。

Study of pH value adjustment using alkaline reagents in the recirculating aquaculture system

The circulating aquaculture system always depends on nitrifying bacteria to transform toxic ammonia into nitrate-nitrogen, and this transformation process will reduce the pH of culture water. So it is very important to maintain the pH value. Most of the research about that are just concerned about the theoretical study without specific experiments. We got some water samples form the circulating aquaculture system, titrated these samples by different alkaline reagents. Through comparing with their titration curve, we found that sodium carbonate and sodium bicarbonate are more suitable to control the pH. Besides, we also found that the water in circulating aquaculture has buffering capacity.