Need help finding a refractometer or hydrometer.

Exotrezy

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I broke my hydrometer recently and need to buy a hydrometer or refractometer replacement. Any recommendations? I don't want to spend too much but people say the cheap amazon refractometers are bad.
 

Aaron75

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That over a refractometer? Could you send over a link?
Yes, no possible user error, only have to compensate for temp. Easy to read. Only downside is their size and how delicate they are. With a refractometer you should calibrate with calibration fluid, then you have to trust/know the calibration fluid is correct. Just Google "tropic marin hydrometer ". Amazon does not sell it.
 

jonelder68

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Aaron75

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Having a 500ml graduated cylinder like above is ideal, buying them separately can save you about $20. A graduated cylinder isn't worth $30
 
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Exotrezy

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Also why would I need the graduated cylinder? Can't i just use the TM hydrometer in the water and squeeze it out the main water normally? Kinda like using a normal hydrometer.
 

Aaron75

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@KStatefan @jonelder68 @Aaron75 Thanks guys for the help. I'll either get that one or maybe get a cheaper hydrometer.
I don't wanna sound like a gatekeeper but I wouldn't recommend a cheaper hydrometer. Too many potential failures. A refractometer is fine but once you calculate the cost of it and fluid you get close to the cost of one of the most accurate pieces possible.
 

Aaron75

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Also why would I need the graduated cylinder? Can't i just use the TM hydrometer in the water and squeeze it out the main water normally? Kinda like using a normal hydrometer.
You dont take water out. It floats in water like a bobber. I only used the hydrometer when I was mixing saltwater in 5g buckets. Now I just turn flow off in the tank or my mixing brute and float it.
 

jonelder68

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Also why would I need the graduated cylinder? Can't i just use the TM hydrometer in the water and squeeze it out the main water normally? Kinda like using a normal hydrometer.
IMG_8177.jpeg

It was water change day so I took a photo for you. Take water sample in cylinder that’s heated to 77 degrees. Then slowly lower hydrometer in. It will float at the level marking on the “stem” to what the salinity is. Hopefully that makes sense.
 
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Exotrezy

Exotrezy

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You dont take water out. It floats in water like a bobber. I only used the hydrometer when I was mixing saltwater in 5g buckets. Now I just turn flow off in the tank or my mixing brute and float it.
Yeah so can’t I just turn off the flow and have it float instead of buying another thing like a graduated cylinder and floating it in that?
 
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Exotrezy

Exotrezy

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IMG_8177.jpeg

It was water change day so I took a photo for you. Take water sample in cylinder that’s heated to 77 degrees. Then slowly lower hydrometer in. It will float at the level marking on the “stem” to what the salinity is. Hopefully that makes sense.
My tank is heated to 78. Can’t I just take the hydrometer and pop it into the tank and have it float around with no flow?
 

jonelder68

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Yeah so can’t I just turn off the flow and have it float instead of buying another thing like a graduated cylinder and floating it in that?
I’d suppose? But in a graduated cylinder is much easier and safer. It’s glass and very fragile! So could possibly shatter while in the tank by bumping into something. It’s full of lead bb weights. So not really worth the risk.
 

Get Salty

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I broke my hydrometer recently and need to buy a hydrometer or refractometer replacement. Any recommendations? I don't want to spend too much but people say the cheap amazon refractometers are bad.
A lot of suggestions you will get. I have used bobbers since the 80’s. Some say the label slip or not accurate. I use them for tank checks and making make up water. Old school I am.
 

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You guys are making this measurement way to scientific. The temp error correction factor on the TM Hydrometer is really insignificant in the real world. I agree it is the "Gold Standard" and I have one but would never recommend one for everyday use. They are simply too delicate. I only use mine to verify my Hanna (which always reads low, BTW) so I can apply a correction factor. Years ago, I used a simple Instant Ocean box type and unless you're planning on doing Hyposalinity, I would just go with something inexpensive.
 
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Exotrezy

Exotrezy

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I’d suppose? But in a graduated cylinder is much easier and safer. It’s glass and very fragile! So could possibly shatter while in the tank by bumping into something. It’s full of lead bb weights. So not really worth the risk.
Ok, thanks. I will just use a seperate small little container that I can float it in.
 

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