Hydrometer vs. Refractometer

A refractometer. I purchased from my lfs. Payed around $45 I believe.

 

gotta test the new batch of SW too

(although i always do this... sometimes I wonder ... bc I do always put in the exact same amount of mix into my bucket...)

IMO, you can catch a SG drop (or rise) of 1 point before your livestock will tell you anything... by the time they react, it will be a few points off already (in general). Using the "i measure SG with my eyeballs method" doesnt seem very good to me...

 

I seldom ever do water changes though. Just top off. Only once in awhile when I need to add some SW due to my skimmer.

 

Was using a swing arm that was about .003 off. I now use a refractometer from drs. foster and smith. Works great. Be sure to get the calibration fluid for it.

 

Have both and no diffrence at all. I must have got a swing arm.

 

Refractometer, only way to be sure. They're cheap, especially compared to how much money most people stand to lose if you mess up your salinity too much. Of course some people's tanks are more susceptible to problems caused by salinity fluctuations. A tank full of fish and softies is probably a good example of a tank that needs less precision since they probably aren't as picky as others and can make a comeback relatively easy. You aren't likely to get a whole colony going poof from a bad swing like you might with other types of coral or really sensitive fish.

The thing I hated most about the swing arm was getting rid of bubbles on the swing arm, that is what took the most time, being careful about that, also the cleaning procedure was a hassle, I love my refractometer.

 

I knew the peanut gallery would chime in on that one

You forgot to add steps 14-17.

scratch your head, wonder if that weird smell is the tank or you, wipe your hands off, and then almost drop the hydrometer.



I can't say much for most hydrometers, but mine is consistently off by the same amount, so it works great for what I use it for.

For everything else, that really matters though, I use the refractometer

 

chiming in on hydrometers..... there has to be hydrometers out there that are as accurate as a refractometer.

Most (if not all) of these hydrometers sold at lfs and web are under $10 and are POS's. Lets be honest.... the newbie ratio to intermediate/advanced reefers my guess would be one sided in favor to newbies. So a newbie will spend the $10 on a hydrometer than a refractometer. So my point being is they are made cheaply with newbies in mind. Newbie will spend $10 before $50 (avg) on a refractometer.

Just my opinion.

Im sure theres high quality hydrometers that are as accurate as refractometers.

calibration fluid should be ro/di water at 1.000. why buy solution?

 

if it reads low, you wouldn't see this with RO/DI. It would just read 0.

with a solution you have a "real" known number, so if it is off in either direction, you will see it.

at least, that's how i understand it...

 

i have a milwaukee hydrometer..... and if you put ro water (1.000) it can possibly go below 1.000 if its out of calibration. On mine theres a screw to adjust to put back at 1.000 if the blue line is above or below with ro water at 1.000.

Not sure how all refractometers are. But thats how mine is. I think its a better number(1.000) than solution (x) that my have evaporated throwing off that x number.