How about Chuangxing CR-30R adjustable air pump?

Generally speaking, star-making things have a characteristic, that is, the power loss is more serious, and it is easier to use when it is new. As time went on, the strength began to weaken after a few months. This is true for both filter cartridges and air pumps.

However, the noise is ok. I use Chuangxing more domestically, but other brands are worse.