Stepping out of biological control and into chemical eradication, we have the option of using Fenbendazole. This is not a bad option if you do not have a lot of inverts and corals. Reefers have diluted veterinary Fenbendazole to use in their reef tanks. The result is no more digitate hydroids. However, being a wormer, it also has the potential to kill all coral with a ‘digitate’ like structure. This includes Green Star Polylp, Xenia and some LPS. It will also kill all worm-like creatures such as Feather-dusters, Vermetid snails. Inverts should be completely removed too to limit the risk to them.
Cloverleaf have released a product called Wormer+. Although this product is marketed at freshwater fish and internal worms, it has the same active ingredient of the veterinary wormer, Fenbedazole.
Caution should be used if you intend to use this product, or any product containing invertebrates.