newreefguy6868
New Member
Could anyone tell me what a good specific gravity in a refractometer would be for a freshwater tank?
SG for freshwater?
- Thread starter newreefguy6868
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534116623686
New Member
Are you talking about how some freshwater fish require salt? couse thats actually a good question I'am curious myself. I know your supposed to add about 2 table spoons of salt for every 30 gallons, but do not know what SG should be? Anyone?
chipmunkofdoom2
Well-Known Member
I think if I recall most people recommend a tablespoon for every 5 gallons. It should say on the salt package. Be sure you get aquarium salt for freshwater tanks.. don't use salt mix we use for reefs. You can use Kosher salt from the grocery store so long as it has NO additives.
Not sure what specific gravity that is though. You can try it out if you want, mix up 5 gallons of water and add a tablespoon of salt and see where you're at.
Not sure what specific gravity that is though. You can try it out if you want, mix up 5 gallons of water and add a tablespoon of salt and see where you're at.
It will still read zero. It takes a lot of salt to change the SG. The purpose of adding salt to a freshwater FISH ONLY tank is for prevention and treatment of several freshwater fish diseases. It also helps heal injuries and such. I do not recommend the use of it in fresh water FISH ONLY systems though. Stress Coat products have the same healing abilities, and also helps to keep the uptake of chemical imbalances in check. Salt in FW systems is not allowed for many fish also such as scaleless fish that cannot tolerate it. I am stressing FISH ONLY because planted tanks will not do well either from salt being added.
reefjitsu
Active Member
It should not be zero. I will assume that 1.000 is meant by this, saltwater is around 1.023. It still should not be 1.000, that number is for pure water and "fresh water" is not "pure 100% water" by any means.
"Fresh water" is a really vague term that means nothing other than "not seawater" . FW fish come from diverse habitats with different water chemistries. The answer to the question depends on the type of fish kept.
"Fresh water" is a really vague term that means nothing other than "not seawater" . FW fish come from diverse habitats with different water chemistries. The answer to the question depends on the type of fish kept.
Correct and not. It should be reading on a refractometer SG 1.000 or as I stated above 0 ppt. Same thing. Sorry, I forgot to add the ppt.
Brackish water is between a SG of 1.000 and 1.022>
There is salt in 97% of all water including fresh water but you will not be able to read it on a refractometer.
reefjitsu
Active Member
It still should not be 0 ppt. That is pure water and is not suitable for fish of any type. Pure water should only be used for top offs or to mix with other chemicals to make the proper solution to support the organisms you are trying to keep.
The point I am trying to get across is that "fresh water" is not pure water. It is a solution consisting of varying proportions of chemicals just like salt water.
BTW, specific gravity is not a measure of how much salt is in the water. Salinity affects the specific gravity, but so do other chemical factors. Temperature also plays a role in specific gravity but does not change salinity. Your specific gravity can be spot on, and your salinity be low.
The point I am trying to get across is that "fresh water" is not pure water. It is a solution consisting of varying proportions of chemicals just like salt water.
BTW, specific gravity is not a measure of how much salt is in the water. Salinity affects the specific gravity, but so do other chemical factors. Temperature also plays a role in specific gravity but does not change salinity. Your specific gravity can be spot on, and your salinity be low.
Rhodes19
Active Member
Are you being sarcastic or am I interpreting it that way?
Your interpreting it that way. Paul's question is a good one. So far we know very little about why the question was asked.
The question was as stated. The answer is zero or 1.000>
Your not going to read anything higher then that with fresh water and a refractometer.
Newreefguy6868 is just setting up his/her first reef from the 13 posts he/she has made so far. The original post was either asking about RO/DI or they meant for a reef tank not a freshwater tank.
If that was the case then to answer the question properly the answer would be not to deviate away from a salinity of 35 ppt (specific gravity = 1.0264; conductivity = 53 mS/cm).
Shesh, I used this answer for three threads today already!
If that was the case then to answer the question properly the answer would be not to deviate away from a salinity of 35 ppt (specific gravity = 1.0264; conductivity = 53 mS/cm).
Shesh, I used this answer for three threads today already!
sambrinar
Well-Known Member
Soo guess what.. it will read 0... taa daa.. question answered..
Newreefguy6868 is just setting up his/her first reef from the 13 posts he/she has made so far. The original post was either asking about RO/DI or they meant for a reef tank not a freshwater tank.
If that was the case then to answer the question properly the answer would be not to deviate away from a salinity of 35 ppt (specific gravity = 1.0264; conductivity = 53 mS/cm).
Shesh, I used this answer for three threads today already!
Huh?? the original question in THIS thread was the SG for a freshwater tank.. which has been answer if a multitude of ways.. LOL
Soo where is the original poster of the question... PEM did have a good question.. what are you putting in the FW tank, and what made you inclined to ask and spark such an interesting discussion??
My point is Brenda that the word Fresh was typed in error. IF you go back over the past 13 posts Newreefguy6868 has made all the questions have to do with setting up a reef tank, what the SG is and about hydrometers. IT is obvious that this person is setting up there first reef tank not a freshwater tank. They also might have been asking about the freshwater starting point reading. If that is the case then the answer was answered many times already.
OK enough time wasted on this! LOL!
OK enough time wasted on this! LOL!
Rhodes19
Active Member
Rhodes19
Active Member
Quote:
Originally Posted by PEMfish
O ppt. What did you do that made you so inclined to find out?
What kind of fish do you have, any live plants.
Are you being sarcastic or am I interpreting it that way?
PEMfish,
I just reread your comment and realized it was a question for OP. When I originally read it I thought it was in response to Frankie's previous post hence my question. I read it out of context. I'm Sorry.
Chris
Originally Posted by PEMfish
O ppt. What did you do that made you so inclined to find out?
What kind of fish do you have, any live plants.
Are you being sarcastic or am I interpreting it that way?
PEMfish,
I just reread your comment and realized it was a question for OP. When I originally read it I thought it was in response to Frankie's previous post hence my question. I read it out of context. I'm Sorry.
Chris