New 25g Blue Glow in the Dark Pebbles,luminous,nigh light fish tank home garden by Plola Quantity : 25 G it becomes highly visible, lasting at least 8 hours, the strongest glow is produced during the first 30 minutes of darkness, the most critical period following a power failure or other emergency. If you want to paint something, please tell me. Delivery time: By Airmail: Generally, delivery to USA takes about 10-35 days. Delivery to Canada,AU, UK, and other European countries takes about 14-28 days.