OASE CrystalSkim 350 Surface Skimmer for Freshwater and Marine Aquariums – Compact Internal Filter for Film Oil and Debris Removal, Quiet, Adjustable Flow, Shrimp-Safe, for Tanks up to 92 Gal / 350 L

One morning I noticed that thin oily film forming on the surface of my tank — the kind that makes even crystal-clear water look dull under light. It bothered me more than it should have. I added the OASE CrystalSkim 350 Surface Skimmer, and within a short time the surface looked noticeably cleaner and more reflective. 🌊 Surface Film & Debris Removal This is where the CrystalSkim really shines. It pulls in surface film efficiently without creating a whirlpool effect. Within the first hour, that hazy layer was mostly gone. Over a few days, the water surface consistently stayed clearer, which improved overall light penetration and shimmer. 🔇 Quiet Operation For something constantly running at the surface, it’s surprisingly quiet. There’s a soft hum if you’re standing right next to the tank, but it blends into normal aquarium background noise. No rattling or harsh suction sounds. 🔄 Adjustable Flow The adjustable intake is useful. You can dial it down if you have a smaller tank or sensitive livestock, or increase it for heavier biofilm situations. I appreciated being able to fine-tune it instead of dealing with fixed, aggressive suction. 🦐 Shrimp-Safe Design This was important to me. The intake design prevents shrimp or small fish from getting pulled in, and I’ve seen no issues with curious invertebrates exploring near it. That peace of mind matters in planted or shrimp-focused setups. 📏 Size & Fit It’s compact and doesn’t take over the tank visually. Compared to some bulky surface skimmers, this one blends in fairly well. It works for tanks up to 92 gallons, but it doesn’t feel oversized in mid-sized aquariums either. 💰 Value for Money OASE equipment tends to sit in the premium tier, and this follows that pattern. It’s not the cheapest surface skimmer available, but the build quality, quiet performance, and consistent film removal justify the investment if surface clarity matters to you.

Bye bye duckweed! If you have duckweed in your tank and want it gone, this is a great addition to that battle. You have to have patience, though. I got the 350 and I’m sure the 600 would’ve cut the time it took but it still worked great. First, let’s address the bubbles that is mentioned in other reviews. Yes, it will cause bubbles but that is determined on how you position the mount to the water line. The further down you place the mount so the top is slid up some, you won’t have bubbles. But, if you want it to work like an air stone, move the mount higher. Second, duckweed removal. Don’t use the blue filter that comes with it. Put a small amount of poly fill in it instead. You will go through a lot but that’s better than trying to clean the blue filter each time. Turn your regular filter off. You don’t want that continuously pushing duckweed down into the tank. Fill your tank to the top of your trim if you have any. Scrape out as much duckweed as you can and remove any other floating plants you want to keep. Then just turn it on. It’ll suck up a ton of duckweed. When it gets full, remove the unit from the mount and tank before unplugging it. Unplug it first and all the duckweed will float right back in the tank. Move the unit around the tank when needed and make sure to scrape around the trim with your finger to loosen up and stuck duckweed. Lastly, take some water out the tank and you’ll notice more duckweed. Keep with the process and soon you’ll be grabbing random pieces with a net. Good luck! Lastly, the color is grey, the mount is very sticky, the unit is very easy to use and fits perfectly in the tank.

I maintain several planted freshwater aquariums with a variety of aquascapes, and I own a few of these surface skimmers. This model has a nice adjustable flow, runs fairly quietly, and does an excellent job clearing biofilm from the water’s surface. However, it has a frustrating habit of catching on its own power cable, causing the unit to sit too high or too low in the water—both of which make it ineffective. I often have to fiddle with the cord and reposition the floating ring to keep things working smoothly. Still, for the price, it’s a solid value—just wish the cord management was better designed.

This is actually one of the best surface skimmers I've owned and to be fair to other manufactures has a lot to do with design improvements over the years. Some others I've used in small tanks are: Eheim Skim350 (excellent skimmer but not for small fish unless install custom netting over the inlet); AquaNeat (budget price, decent but not best); ADA Vuppa II (quality built, pricey, skims well, motor mechanism prone to failure). What I like about the Oase 350: excellent skimming, inlet/outlet designs, pricing, functionality.

Not upto the mark.

Amazing product, however this listing is for the US version, which is 110V and UAE has 220V so this device will just overload and get damaged mine worked for 3 days before giving up, I did not notice the voltage rating sadly, Amazon was nice enough to refund me. Look for the UAE version or a 220V version of the same skimmer, it was amazing when it worked.

Excelente compra, lo recomiendo.

Great piece of kit and cleared the surface up in just minutes as I had seen it shown on YouTube.

Was soll man dazu groß schreiben, super Skimmer, hochwertig verarbeitet und leistet beste Arbeit in meinem 570 Liter Becken.