Practical examples and maintenance of circulating water protein skimmer!

(1)Key points for operation and maintenance of protein skimmer

1. Air intake adjustment

According to the water quality and flow rate of the circulating water, the air intake of the protein skimmer should be properly adjusted. If the air intake is too small, the number of bubbles generated is insufficient and the organic matter cannot be effectively adsorbed; if the air intake is too large, the water body may be excessively disturbed, affecting the living environment of the aquaculture organisms, and the foam may overflow the skimmer. For example, for a medium-sized recirculating aquaculture system, the air intake of the protein skimmer can be adjusted between 0.5 and 1.0 cubic meters per hour.

You can adjust the air intake by observing the foam production. The ideal foam should be fine, stable and light in color. If the foam is too coarse or unstable, you may need to reduce the air intake; if the foam is little or disappears quickly, you may need to increase the air intake.

2. Water level control

It is important to keep the water level in the protein skimmer stable. Water levels that are too high or too low will affect the separation effect. The water level is usually controlled by adjusting the height of the water outlet or using a water level controller. For example, when installing a protein skimmer, set the water outlet height to about two-thirds of the skimmer height, which ensures that the foam has enough time and space to form and separate.

3. Cleaning and maintenance

Regular cleaning of the protein skimmer is the key to maintaining its good performance. Organic matter in the water will settle inside the skimmer, especially in the bubble generating device and the foam collecting device. For parts that are easily clogged, such as the nozzle of the needle-type protein skimmer, it should be cleaned at least once a week. When cleaning, you can rinse with clean water. For stubborn dirt, you can use a mild detergent, but be careful to rinse thoroughly to avoid detergent residues that may harm the cultured organisms.

Check the tightness of the equipment and the working condition of the bubble generating device. If there is any leakage, repair it in time, because leakage will affect the generation and separation of bubbles. At the same time, check the operation of the motor (if any), water pump and other equipment to ensure that they are working properly.

(2)Actual combat case

1. Farm background:

There is a large fish farm with a water area of about 10,000 cubic meters, mainly breeding grouper and other species. The farm adopts a recirculating water aquaculture system with a high breeding density, breeding 40-50kg of fish per cubic meter of water. Since marine fish have strict requirements on water quality, especially the protein and ammonia nitrogen content in the water, water quality management is very important.

2. Application of protein skimmer:

Several large needle-type protein skimmers are used in combination. The processing flow of each protein skimmer is 200-300 cubic meters/hour, and the air intake is controlled at 50-80 cubic meters/hour. The specially designed needle-shaped nozzle produces tiny and dense bubbles, which effectively absorb organic matter in the water.

• Effect analysis:

When a protein skimmer is not used, organic matter in the water causes the water to become turbid, dissolved oxygen is consumed quickly, and ammonia nitrogen and nitrite concentrations rise rapidly. This results in suppressed growth, dull fish color, a higher incidence of disease and a mortality rate of 20% - 30%. After using the protein skimmer, the water quality has been significantly improved, the water transparency has been improved, the concentrations of ammonia nitrogen and nitrite have been effectively controlled, the fish have grown well, the mortality rate has been reduced to 10% - 15%, and the quality of the fish has also been improved.