Emergency - Specific Gravity ???

vikki7

Member
Thomas are you around?
I noticed my maroon and gold Clown was swimming at the bottom of the tank.
I took a water reading and my specific gravitiy tested at 1.027
WHY would it jump that high?
My water evaporation is only about 1/4 to 1/2 down at the most 1 inch and I doubt it
is that low..........
One other occurance that happened lately is I had a Purple Leather dye on me.
There is green slimy algea on my live rock too and it is a weird looking kind.
Almost a fuzzy looking web look, but not the hair algea....
HELP please... :help:
 

bigarn

Active Member
What is your SG usually at? More importantly, what is the salinity reading? A good salinity for a reef tank is around 35ppt. Are you testing the saltwater before adding it during water changes? Are you topping off with fresh RO water? :D
 

vikki7

Member
First, I have a 12 gallon Nano tank....
My Specific Gravitiy is normally arount 1.023 - 1.024
The
salinity is reading at the low side of the 36ppt mark.
Are you testing the saltwater before adding it during water changes?
YES I AM......... I use the saltwater and purchase it already mixed...
Are you topping off with fresh RO water
I always top off when I need too.
I just don't understand the JUMP in SG ..... it has never done that before......
I have LIVE ROCK, Live Sand and one Maroon and Gold Clown in my tank now...
I am getting ready to purchase a clean up crew but the store here in my town does
now have any in stock..
So, I need help as to where i can get the BEST online......and try that way.......
I am going to have an anemone again so I dont want any critters that will mess with him.
I have some RO water I am heating up and getting ready to top off the tank.
But, is there anything thing else I need to do?
Thanks for you help.
Whats next.....?
 

bigarn

Active Member
If this is going to be a reef tank, 36ppt isn't bad. Forget about the SG... salinity is the important reading IMO. If you want to lower the SG you have to make sure it's lower than what you have when you do a waterchange. Is whoever testing it using a hydrometer or refractometer? The refractometer is much more accurate. :D
 

thedocta

Member
OK are you using a reftractometer or a hydrometer? Hydrometers often are .003-.005 low. Get a refractometer if you don't have one because they are a great investment for about 45 bucks. Also it's not the high SG that you should be worried about but the quick change. You want stability. I keep my tank at 1.026 all of the time which is a good idea because it's closer to the real SG of the oceans. If I were you I'd drop the SG to 1.026 and leave it there. Just my opinion.
 
J

jacob_poly

Guest
I had my tank at 1.029 for a while before I realized it. And the reason for that was because I used a hydrometer that had poor precision and also too wide a range. What a wide range does is that it narrows the meaningful limits and so looking at it from above the water it would show one reading, below the water it would show another. And the water actually climbs a little along the side of the glass wall (probably due to capillary effect)...bottom line being that I had no clue which to go by....finally I went to my LFS and got it calibrated against their refractometer and it was 1.029. This value corresponds to a range of 1.024 to 1.029 depending on how I read my hydrometer based on the meniscus. But now I know which meniscus to go by and which angle to view the thing to get a close to accurate reading.
So either get a hydrometer that has a range from 1.015 to 1.030 (rough figures) instead of a hydrometer that has a range of 1.00 to 1.045. Or get a refractrometer.
But none of my fish really got affected with the higher specific gravity. So 1.027 I think is ok (perhaps need to lower it a shade). But that all depends on if 1.027 IS 1.027. After calibration if you find that 1.027 is actually 1.031, then you have to worry....
 

salty cheese

Active Member
Originally Posted by Vikki7
First, I have a 12 gallon Nano tank....
I am going to have an anemone again
:eek:
Originally Posted by Vikki7

But, is there anything thing else I need to do?
Buy A bigger tank. :happyfish
 

vikki7

Member
Originally Posted by jacob_poly
I had my tank at 1.029 for a while before I realized it. And the reason for that was because I used a hydrometer that had poor precision and also too wide a range. What a wide range does is that it narrows the meaningful limits and so looking at it from above the water it would show one reading, below the water it would show another. And the water actually climbs a little along the side of the glass wall (probably due to capillary effect)...bottom line being that I had no clue which to go by....finally I went to my LFS and got it calibrated against their refractometer and it was 1.029. This value corresponds to a range of 1.024 to 1.029 depending on how I read my hydrometer based on the meniscus. But now I know which meniscus to go by and which angle to view the thing to get a close to accurate reading.
So either get a hydrometer that has a range from 1.015 to 1.030 (rough figures) instead of a hydrometer that has a range of 1.00 to 1.045. Or get a refractrometer.
But none of my fish really got affected with the higher specific gravity. So 1.027 I think is ok (perhaps need to lower it a shade). But that all depends on if 1.027 IS 1.027. After calibration if you find that 1.027 is actually 1.031, then you have to worry....

Thanks that info really helps...
I am going to the fish store tomorrow to see what type instruments they have.
Now I am off to find a good clean up crew...
Got any info on the best guys to use? I have alot of iky green algea all of a sudden.
But, that is partly my fault..... there is NO clean up crew in this town to purchase....
So now I need to go online to buy.....
 
T

thomas712

Guest
Originally Posted by bigarn
If this is going to be a reef tank, 36ppt isn't bad. Forget about the SG... salinity is the important reading IMO. If you want to lower the SG you have to make sure it's lower than what you have when you do a waterchange. Is whoever testing it using a hydrometer or refractometer? The refractometer is much more accurate. :D
Agreed. You see the SG will change with heat or cooling down, the salinity will not change.
You might also want to clean your hydrometer with some white vinegar and then test again. Make sure all bubble are off of the swing arm. Also check the temp and record your findings.
My refractometer is an indespensible peice of equipment. Well worth the money.
Thomas
 
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