Stream2Sea Professional Mask Defog Review

My go-to anti-fog solution for both freshwater and saltwater dives. It outperforms spit and baby shampoo, holds up better if your mask floods or gets dunked, and is the only defog I trust to be safe for aquatic environments. Not cheap, but absolutely worth it.
Overall Score: 8.3 / 10
Pros & Cons
Pros | Cons |
---|---|
Reliable and consistently effective | More expensive than DIY options |
Resists rinsing when mask is dropped or flooded | Harder to find in stores |
Lab-tested safe for marine and freshwater environments | Does not last for multiple dives without reapplication |
Why I Chose Stream2Sea
I’ve tried spit, baby shampoo, and random boat defogs over the years, but I was always chasing something that just worked without needing to reapply constantly or worry about what chemicals I was putting into the water. As a Chicago-based diver, most of my dives are in freshwater quarries or Lake Michigan, and I wanted a defog that wouldn’t fail during cold or rushed kit-ups. Stream2Sea checked those boxes and has never let me down. I’ve shared it with students and buddies who used to rely on baby shampoo or “boat juice,” and every single one reported a noticeable improvement.
Performance in the Water
- Fog Prevention: Very effective when applied correctly. I’ve never had a fog issue with it when using a pea-sized amount.
- Flood Recovery: It holds up better than baby shampoo if the mask is dropped in water during setup or floods during the dive.
- Skin and Eye Comfort: No irritation reported, even after repeated use in sensitive freshwater environments.
- Environmental Safety: Stream2Sea is the only option I trust around aquatic ecosystems because it’s actually tested and documented for safety.
Verdict
Stream2Sea has become my default mask defog. It’s always in my kit and gets passed around often because it just works better. While it’s not magic and still requires reapplication for every dive, it’s reliable enough to be worth the extra few cents per dive.
Would I buy it again? Yes. This is the only defog I actively recommend and repurchase.
Deep Dive into the Score
Scoring System: Each category is scored out of 10 and weighted by importance. This model is used consistently across all gear reviews for transparency.
Category | Score (0–10) | Weight | Weighted Score |
---|---|---|---|
Function & Performance | 9 | 30% | 2.7 |
Ease of Use | 9 | 20% | 1.8 |
Versatility | 6 | 15% | 0.9 |
Durability & Build Quality | 7 | 15% | 1.05 |
Value | 8 | 10% | 0.8 |
Brand Trust & Transparency | 10 | 10% | 1.0 |
Total | 8.25 |
Rounded Display Score: 8.3
Deep Dive Score Explanations
- Function & Performance – 9: Excellent anti-fog performance in real-world conditions. Rarely fails when used properly.
- Ease of Use – 9: No dilution needed. Squeeze, rub, rinse, and go.
- Versatility – 6: Needs to be reapplied for each dive. Not ideal for all-day multi-dive charters without a rinse and reapply break.
- Durability & Build Quality – 7: Nozzle works fine and travel-safe cap is secure, but nothing special about the bottle.
- Value – 8: Yes, it’s more expensive than baby shampoo, but the per-dive cost is still just a nickel and worth every cent.
- Brand Trust & Transparency – 10: Stream2Sea publishes full ingredient lists and third-party test results. No greenwashing.