Fluval Sea Hydrometer for Aquarium, Medium

I’m a Fluval tank owner so I trust the results of the hydrometer. My LFS uses the same one so it was a no brainer to get. Very important as part of your maintenance in your saltwater aquarium.

does not work at all. just by a cheap refractometer it will do you much better.

Don't listen to the people that say it goes high in tap water. It does, but that's because that's not how it's meant to be used. Get it in your tank and get all of the bubbles out and it works great. Mine was getting towards the top of the green area so I topped of my tank with RODI water and I could watch the gauge go down as the salinity went down. Great accessory to have in my tank.

if you need to read your salinity quickly it's easy to use but I would have rather bought a refractometer, but overall it is still a good product and i would recomend

Ease of use but we must remember to rinse when done to maintain accuracy in the future.Helps ensure water cycles are correct when replacing salt to water that was removed for the aquarium. Love it!

I already have one of these and it works great. I have a couple specimen specific tanks so I wanted to get one for each tank so I'm not always having to move them or put my hand in to do it. I ordered 2 more and both these new ones don't work. Rinsed them with fresh water and even rinsed them out with vinegar and still they don't work. I can see air bubbles on the armature and tried gently taping as per the instructions, the bubbles don't disperse. I never had this trouble with the one I have, it worked great from the get go and I've loved having it. I've had to rinse it once and awhile and even had debris get in it so I'd rinse it out and it was fine. I have a regular hydrometer that I use when mixing salt water so I've compared my first one with it and it's alway been pretty accurate. It was a no brainer to get the same brand, guess I was wrong. I'm disappointed with this purchase. I'll try soaking them in vinegar like other people suggested but more than likely I'll return them. If soaking works then I'll update my review.

Remember to clean with vinegar to remove calcium buildup with fresh water rinse and salt water salt buildup. It will make or break you level gauge reading.

Glad I read the review where the person suggested putting it in vinegar for 2 hours. I let mine soak for about an hour to get it to actually work. It just wanted to float to wherever the water level was on it. I almost gave my first negative review, but the vinegar saved it. Put it in vinegar and it actually started to work. Can't verify the accuracy percentage.I just need this for a baby nerite snail tank. If they die, I won't be at a loss for money. Would not suggest this if you're doing a serious tank that needs close monitoring of the levels unless you have a high quality one you can compare the reading accuracy with.