Adjustment of the aquaculture water: the supernatant in the aeration tank is turbid and yellowish. First time encountering this type of water

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In the air flotation, UASB, and AO aeration tanks, the supernatant is extremely turbid and yellow in color. The COD level of the influent water is around 1000, while the ammonia nitrogen level is 400. The water volume is half of what it should be according to the design specifications. The aeration duration is 45 hours, with 15 hours of anoxic conditions. Intermittent aeration was tried, as well as the approach of passing the water directly to the aeration tank after some physical and chemical treatment while keeping aeration ongoing; however, none of these methods were effective, even with a sludge load of around 0.15. Strangely enough, the pH of the influent water increased from 7.5 to 8.5 without the addition of alkali, indicating strong reverse digestion – could this be due to the inhibition of free ammonia during digestion? At present, there are no tests conducted for COD and ammonia nitrogen in the aeration tank; the yellowish and turbid supernatant makes it difficult for me to carry out tests. It’s quite unusual as this is my first time dealing with such water. Please, guys, help me figure this out