Diatoms are a silicon based algae (phytoplankton) which can out-compete the growth of other types of algae, including those toxic forms that cause HAB's.
As well as preventing toxic algae from growing, Diatoms are also good as they provide nutrients for fish whilst also increasing oxygen in the water.
Whilst the consumption of Diatoms prevents them from becoming a nuisance, if the level of Diatoms drops too low, their positive effect is reversed.
A low Diatom population results in the growth of toxic algae as nitrogen is no longer converted into dissolved oxygen but instead is released as CO2.
In order to effectively grow and control Diatoms as a HAB prevention method, a product named Nualgi can be used.
Nualgi claims to help Diatoms grow rapidly in fish ponds and prevents levels from dropping too low.
You can find out more about how to use Nualgi by clicking here.