As someone who's battled flatworm infestations in my reef tank, I can confidently say Salifert Flatworm eXit is one of the most effective treatments available. The product works exactly as advertised - within 30 minutes of dosing, I watched those pesky flatworms start writhing and dying off. It was oddly satisfying after months of struggling with these invaders.

The pros are clear: this stuff is incredibly potent against flatworms. In my 120-gallon system, it completely eradicated a moderate infestation in one treatment. Unlike some other methods (looking at you, Springer's damsel), it actually solves the root problem rather than just nibbling at the edges.

However - and this is a big however - you MUST follow the instructions precisely. I learned the hard way that flatworms release toxins when they die en masse. My first treatment caused noticeable stress to corals for about 24 hours, though everything recovered fully after a large water change and carbon filtration.

The product has some limitations: it doesn't affect eggs, so multiple treatments may be needed. Some users report diminishing effectiveness on subsequent doses. And crucially - it's NOT for freshwater tanks (one poor reviewer learned this the hard way).

My advice? Have plenty of saltwater ready for changes, run carbon aggressively, and consider treating rocks separately if you have a severe infestation. While not perfect, when used carefully, Flatworm eXit is still the most reliable weapon in our flatworm-fighting arsenal.