# How Do IHow Do I Read My Refractometer?

#### Darn it

##### New Member
Member
I guess I need a refractometer for math dummies.
Got an ATC refractometer because it is cheaper than a salinity meter and has no batteries....and well I thought it would be easier to read than it is.
I'm guessing I'm in the right forum. Not doing a reef tank but salting a pond.

I thought this would help me calculate exact gallons of my pond but I can't even understand the readings let alone do the math on the gallons.

the left side (D 20/20) scale goes from 1 to 1.07
the right side (0/00 )goes from 0-100. I'm not stupid but math, aargh! I read the booklet and I'm still not getting it.

It looks like the right side would be easier to read so lets go with that. What should the right side ( 0/00) read at:
.1% salinity
.2%
and .3%
Thx for being patient with me.

#### Fanatic

##### Fishlore VIP
Member
I am absolutely no expert with saltwater, so let's hope our salty fishkeepers can help you today.

#### Culprit

##### Fishlore VIP
Member
Darn it said:
I guess I need a refractometer for math dummies.
Got an ATC refractometer because it is cheaper than a salinity meter and has no batteries....and well I thought it would be easier to read than it is.
I'm guessing I'm in the right forum. Not doing a reef tank but salting a pond.

I thought this would help me calculate exact gallons of my pond but I can't even understand the readings let alone do the math on the gallons.

the left side (D 20/20) scale goes from 1 to 1.07
the right side (0/00 )goes from 0-100. I'm not stupid but math, aargh! I read the booklet and I'm still not getting it.

It looks like the right side would be easier to read so lets go with that. What should the right side ( 0/00) read at:
.1% salinity
.2%
and .3%
Thx for being patient with me.
How does knowing the salinity calculate the exact gallons of the pond?

Its a refractometer like this right? Basically, the left side is your Specific Gravity. Which is what we mostly use. We keep our reef tanks at 1.027. The right side is your ppt, or parts per thousand. We keep ours at around 35 ppt. I'm not sure what your pool's salinity is supposed to be, but that's what I can tell you. The different sides do the same thing, just different wording.

OP

#### Darn it

##### New Member
Member
Yup. It looks just like that.
Ok so if it reads 1.027 specific gravity and 35 ppt on your tank how do you know what the salinity is? I was looking for a number like .1% or .3% but it doesn't give a %. Maybe 35/1000 =.035%
is that what your salinity is?

Oh there's supposed to be a way to figure out gallons using this thing and a measured amount of salt and measuring the amount of salt it takes as it goes from .1% to .2% . But hey I need to be able to read the thing first.

#### Attachments

• 985 bytes Views: 78

#### Culprit

##### Fishlore VIP
Member
Darn it said:
Yup. It looks just like that.
Ok so if it reads 1.027 specific gravity and 35 ppt on your tank how do you know what the salinity is? I was looking for a number like .1% or .3% but it doesn't give a %. Maybe 35/1000 =.035%
is that what your salinity is?

Oh there's supposed to be a way to figure out gallons using this thing and a measured amount of salt and measuring the amount of salt it takes as it goes from .1% to .2% . But hey I need to be able to read the thing first.
1.027 is our salinity. That's the density of the water. Pure freshwater has a density of 0. 35 ppt is 35 parts per thousand. That's 35 parts of salt to 1 thousand parts water. I don't know what this percentage you're talking about is.

I would think if you measured the salinity of a sample of say 5 gallons, then measured how much salt it took to raise salinity to a certain point. Then you could slowly add salt to the pool, measuring how much salt was added, until it raised it to the same point. Then use how much salt you added to figure out the saliity. Just a guess.