This product is high temperature sinter bubble stone (aquaculture USES coarse sand bubble big, not work rough!, strong and durable, not loose, and not easy to drop slag.For fish or aquaculture, please use medium and large coarse sand head, small cylinder for fine sand, aquarium fish use more appropriate.
1.Soak the product in water for an hour before use
2.If the bubble is too small, you can blow it with your mouth and use it
3. For long-term use, if there is dirt blockage and air bubbles decrease, you can take it out for cleaning and reuse