I started my tank about 4 months ago and I wish I would have found these podcasts back then. Invaluable, thank you so much for doing this!
I've got a quick question about measuring salinity. I've got one of those plastic salinity tests that you fill with water and the little platic arrow points to the specific gravity. I noticed my specific gravity has above what I wanted so over the past week i've put in fresh RO/DI water to help bring it down. I've put in about 7 gallons in a 65 gallon tank and the gravity hasn't changed. I'm a little concerned that this plastic thing is lying to me.. I'm wondering if these things are reliable or should I be using something else to get accurate results.
i use the same test kit for measuring salinity, works ok for me. know that those test kits give you only a ball park figure of your salinity. main thing here is make sure there are no bubles clinging to the arm when reading the results. those bubbles throw everything off. it takes some practice but youll get it.
latez
people have mixed results with them.
i have used them and if properly seasoned and cleaned after each use they can be ok.. others say they are worthless.
the best thing is to get a refractometer, as they are much more accurate.
to lower the salinity you cant just add FW, you need to remove water and replace it with FW, otherwise you will just be replacing evaporated water, and thus maintaining (not changing) your salinity
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Get a good refractometer. I have three different hydrometers, all used. I re-seasoned them and tested them against the SAME tank of water. All three had different readings. My refractometer cost me 45 dollars and I've checked it against calibrated solutions and it reads perfect!
The little plastic thingy is called a hydrometer....
yes, they can be variable and a refractometer would be much more consistent.
However, you can increase the reliability and functionality of your hydrometer by cleaning it with freshwater after use. I regularly fill mine also with vinegar in order to remove all deposits so that the guage can move freely.
thanks, Out of curiosity I picked up a different brand hydrometer and I'm seeing a variance between the two readings of about .002. Of course half the time the new one doesn't work at all... it's going back to the store. Can anyone recommend a good refractometer?
I'll do a full water change tonight and see if I can get it to drop.
I agree with the others that have posted about a refractometer. I picked one up from another site, paid more ~60-70 I think. But you can get a good one in the $40-50 range too. And as Rob said, make sure it's ATC.
My LFS still used a plastic hydrometer (swing arm)...and when I was getting saltwater from them I would make sure they didn't mix it higher than 1.018. Then I'd all salt at home to top it off to the reading I wanted. Now I got my RODI unit hooked up and don't have to buy my water anymore. :-)
__________________ Tank setup 8-5-05
26 gal bowfront
I also use a refractometer. Got it off of ebay for $40. It is so much accurate and a lot less messy. I used a swing arm for a while and found that it was a little cumbersome. It was accurate when I compared it to my refractometer, which I was relieved to find out. I've also read it's a hit or miss with them. I think with dealing with a small tank it's better to use a refracto. Too many swings in salinity due to evaporation and water changes. I check my level all the time just cause it's so easy to use!
i agree, they are so easy, you will be using it al the time..
much less water is used, easy to clean, easier to read, just plain easier..
i got mine for $32 in a group buy..
i also found that my hydrometer was accurate compared to my refractor. (multiple tests on different days...)
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i also found that my hydrometer was accurate compared to my refractor. (multiple tests on different days...)
nice. I guess I never bothered to see how accurate my hydrometer was after I got my refractometer. the hydrometer now sits in a bucket with other odds and ends from differnet power heads and such.
Oh, calibration is easy too....just add freshwater (RODI preferably) and make sure the "blue line" is sitting at 1.000
__________________ Tank setup 8-5-05
26 gal bowfront
I too used to use a hydrometer, but my wife got me a refractometer & I'm glad I got one. My salinity was off from the readings of the hydrometer. Just a note I did season my hydrometer before use.
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