ABSTRACT

Partial water exchange is one of the most common conventional methods used to maintain water quality and aesthetic beauty in recirculating aquarium systems (RASs). However, this method uses substantial amount of water. The ozone-down-flow hanging sponge-up-flow sludge blanket (ozone-DHS-USB) system attempts to be a more responsible method for aquarium maintenance. It eliminates the necessity for water exchange in aquarium by maintaining nitrogen concentrations at a safe level and by reducing yellow substances. Also, the impact of O₃ on the DHS-USB system was investigated. The system was assayed using an on-site freshwater aquarium influenced by ambient temperature ranging from 23°C to 34°C. During ozonation Phases 1 and 3, the colour of the water in the aquarium was successfully maintained below 10 colour units. The 16S rRNA gene analysis of microorganisms in the DHS revealed that constant application of O₃ has caused a decrease in nitrite-oxidizing bacteria (NOB). Nevertheless, NH₃ and ${\mathrm{NO}}_2^{-}$ were maintained within 0.1 mg N L⁻¹, and ${\mathrm{NO}}_3^{-}$ was maintained at 14.6 ± 9.20 mg N L⁻¹ throughout the study. Carps survived for 425 days without any water exchange performed. Our study supports that the ozone-DHS-USB system has a high potential towards creating low-maintenance aquaria.

摘要

部分换水是循环水族箱系统 (RAS) 中用于保持水质和美观的最常见的常规方法之一。然而，这种方法使用大量的水。臭氧下流悬挂海绵上流污泥毯（臭氧-DHS-USB）系统试图成为一种更负责任的水族箱维护方法。通过将氮浓度保持在安全水平并减少黄色物质，它消除了水族箱中水交换的必要性。此外，O _3的影响对 DHS-USB 系统进行了调查。该系统使用受环境温度影响的现场淡水水族箱进行分析，环境温度范围为 23°C 至 34°C。在臭氧化阶段 1 和 3 中，水族箱中水的颜色成功地保持在 10 个颜色单位以下。DHS 中微生物的 16S rRNA 基因分析表明，持续施用 O ₃导致亚硝酸盐氧化细菌 (NOB) 减少。尽管如此，NH ₃和${\mathrm{不}}_2^{-}$保持在 0.1 mg NL ^-1以内，并且${\mathrm{不}}_3^{-}$在整个研究中维持在 14.6 ± 9.20 mg NL ^{-1 。}鲤鱼在没有进行任何换水的情况下存活了 425 天。我们的研究表明，臭氧-DHS-USB 系统具有创建低维护水族箱的巨大潜力。