Gasping Fish – Oxygen Crash

Everyday Life

Hot summer weather is great – but not for pond fish!

With temperatures soaring and sun worshippers making the most of the hottest summer in years, the inevitable thunder storms will follow.

How does this affect your pond?

Prolonged sunny spells can cause massive algae blooms in ponds that have a huge effect on dissolved oxygen in the water. When this is followed by heavy downpours this can also cause an oxygen crash. This can be identified by seeing a sudden change in colour in the algae.

This distress in fish can even cause death if not prevented or treated properly. Fish will be seen ‘gasping’ for air at the top of the pond and in extreme cases lying on their side on the top of the water.

UV treatment of pond water is the most effective way to inhibit algae growth. Disassociating the DNA of single cell algae to prevent it multiplying will reduce growth and minimise algae bloom in ponds. Ensuring a pre-filter of 5 micron is installed before the UV also allows effective pre-treatment of the water prior to UV sterilisation and will reduce ‘shadowing’ whereby bacteria and single cell organisms are shielded from UV light by larger particulate.

Bag filters are commonly used to reduce floating algae in ponds and large tanks and offer a simple, reusable solution to bulk particulate reducing prior to UV sterilization.