United Aquatics T5 4-Pin UV Bulbs

Premium-quality quartz crystal T5 four-pin one end germicidal UV bulbs, designed for ultraviolet clarifiers to eliminate green water in ponds and aquariums. These UV bulbs effectively sterilize single-cell algae, keeping your water garden, koi pond, or aquarium crystal clear and healthy. Compatible with the old Laguna Pressure-Flo Filters (700, 1400, 2100, 3200), submersible Pondmaster UV's, and many more.