THis should probably be added to the FAQ's, but here it is anyway. My SG is 1.024. I hear that this may be a little low. I know the ocean is .028 (apporx), but what is your tank at and why? Do those with mostly coral tanks keep it higher than those with mixed reef tanks? I heard some where that a higher SG was more stressful for fish and that it made it harder for them to breathe. Any advice? My system is a 180 AGA mixed reef, with SPS and numerous fish
What is your salinity???
- Thread starter hurrifan
- Start date
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by Hurrifan:
<strong>I know the ocean is .028 (apporx</strong><hr></blockquote>
Huh? Really?
Mine is at 1.023 steady. The reading is temperature compensated.
[ February 25, 2002: Message edited by: danmhippo ]</p>
<strong>I know the ocean is .028 (apporx</strong><hr></blockquote>
Huh? Really?
Mine is at 1.023 steady. The reading is temperature compensated.
[ February 25, 2002: Message edited by: danmhippo ]</p>
Reefs average about 35ppt or 1.026. Depends though... Red Sea and Persian gulf are about 40ppt.
1.026 is a good baseline to shoot for.
here... read this
http://www.animalnetwork.com/fish2/aqfm/1997/nov/features/1/default.asp
[ February 26, 2002: Message edited by: Steve Richardson ]</p>
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BT-4 Combat
1.026 is a good baseline to shoot for.
here... read this
http://www.animalnetwork.com/fish2/aqfm/1997/nov/features/1/default.asp
[ February 26, 2002: Message edited by: Steve Richardson ]</p>
_________________
BT-4 Combat
You know this was rather an interesting battle for me as well.
I have read that in order to get a true salinity you have to read the Hydrometer and then convert the OHR to density based on Temperature using a table that is provided in a book by Tullock
OK here goes... [Tullock - Natural Reef Aquariums] says " if the Temperature in your tank is 22 degrees Celsius and your hydrometer reading is 1.0230 the conversion factor of (0.0016) should be added to your hydrometer reading resulting in a density reading of 1.0246 then convert the Density to Salinity using another table ends up being a salinity of 33 PPT.
My problem is this if I keep my tank at F-82°(C-28°) and follow his table going with my Observed Hydrometer Reading of 1.0245 and add the conversion factor of .0036 ( Had to guess here because he does not reccomend running a tank at this temp and does not provide table data ) HOLY CRAP am I really running at a Density of 1.028 and a Salinity of 38+PPT - Should I then lower by Observed hydrometer reading using freshwater to 1.020...... I dont think so. After debating this with other reefers and reading the advice I still dont know what the heck to do
I leave my Temp around F82° and my specific gravity around 1.0245+ and have done so since around 1989 or so.
Am I screwing up or ???? and if I correct this scenario will I notice improved growth and color in all life or should I leave well enough alone
[ February 26, 2002: Message edited by: Jawbone ]</p>
I have read that in order to get a true salinity you have to read the Hydrometer and then convert the OHR to density based on Temperature using a table that is provided in a book by Tullock
OK here goes... [Tullock - Natural Reef Aquariums] says " if the Temperature in your tank is 22 degrees Celsius and your hydrometer reading is 1.0230 the conversion factor of (0.0016) should be added to your hydrometer reading resulting in a density reading of 1.0246 then convert the Density to Salinity using another table ends up being a salinity of 33 PPT.
My problem is this if I keep my tank at F-82°(C-28°) and follow his table going with my Observed Hydrometer Reading of 1.0245 and add the conversion factor of .0036 ( Had to guess here because he does not reccomend running a tank at this temp and does not provide table data ) HOLY CRAP am I really running at a Density of 1.028 and a Salinity of 38+PPT - Should I then lower by Observed hydrometer reading using freshwater to 1.020...... I dont think so. After debating this with other reefers and reading the advice I still dont know what the heck to do
I leave my Temp around F82° and my specific gravity around 1.0245+ and have done so since around 1989 or so.
Am I screwing up or ???? and if I correct this scenario will I notice improved growth and color in all life or should I leave well enough alone
[ February 26, 2002: Message edited by: Jawbone ]</p>
I have had several saltwater reef tanks throughout my life and if there is one thing I can say for sure it is if it works for you, regardless of what others might say, then stick with it. Now having said that I am going to play the devil's advocate and state my own 2 cents. Personally I would not run my take at 82 degrees F for a few reasons, mainly if something was to go wrong you have a lot less time to correct the problem before the tank overheats. Furthermore, many of us, and I would assume yourself are not buying fish and or corals from one region of the world. Knowing that we cannot possibly try to meet all their specific requirements, therefore, we must try our best to find a happy medium. Remember unless you are purchasing various creatures from one region of the world the ocean's salinity and temp will not matter unless you are willing to have a seperate tank for each one. Let me elaborate on that point a little more. Yes it is important to pay specific detail to temp and salinity but your tank is not the ocean even though many of us including myself wish it were. Therefore my conclusion is this keep on doing what your doing if it works. Because if it works you found a happy medium for your corals and fish that are (and I repeat) from around the world requiring various temperatures and salinities. Hope this helps.
all temperature considerations aside..........
1.026 due to prescence of invertabrates but especially stars which require 1.025 for proper regulation of their internal hydralic system.
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Disabilities Forum
1.026 due to prescence of invertabrates but especially stars which require 1.025 for proper regulation of their internal hydralic system.
_________________
Disabilities Forum
I do appreciate the input as I learn something every second of every day. I guess I use the 82 degree rule for my tank due to my past experiences with fish disease. ( Supposedley running tanks at a higher temp helps the disease run its course faster) so with that in mind I keep the tanks warmer and deal with the algae growth, So far with this method of temp control I have not had any deseases ( But I dont add fish everyday either so Its not really a controlled experiment now is it ) and to combat the algae I just curculate the water by a factor of 30:1 for every gallon of water I move 30 gallons - Yes this seems like a lot but its not. I prefer many small pumps moving lightly as opposed to large pumps pushing rock around.
I will try anything once and run my tanks at a lower temperature especially if this OHR/temperature conversion table are true.
I will try anything once and run my tanks at a lower temperature especially if this OHR/temperature conversion table are true.
- Location
- Virginia
1.0235 (about). I've heard a lot of arguments over the SG of the oceans, but I've always done 1.0235 so I'm sticking with it. I average 1.023 an 1.024, so I add the .0005 for good measure!
1.0255 is my target, using a Tropic-Marin floating glass hydrometer, with tank temp at 80~82f.
As Steve said, ocean reefs are generally considered as 35 ppt Salinity, or 1.026 Specific Gravity, but this can vary widely from place to place.
Jawbone,
Unless using a calibrated refractometer, most of our aquarium readings are going to be somewhat imprecise. Stability is the key, IMHO. My Tropic Marin is calibrated for 77f but I don't worry about the temp conversion as long as the readings are consistent.
Dick
[ February 26, 2002: Message edited by: FishDaddy ]</p>
As Steve said, ocean reefs are generally considered as 35 ppt Salinity, or 1.026 Specific Gravity, but this can vary widely from place to place.
Jawbone,
Unless using a calibrated refractometer, most of our aquarium readings are going to be somewhat imprecise. Stability is the key, IMHO. My Tropic Marin is calibrated for 77f but I don't worry about the temp conversion as long as the readings are consistent.
Dick
[ February 26, 2002: Message edited by: FishDaddy ]</p>
Fish Daddy OK yes I agree the stability is great, but that does not touch on the Conversion factor. after looking at my post I realized that I may have missed a decimal place and would not have such a drastic difference between Observed Hydrometer Reading and Actual Salinity but the point being that relying on the reading to be a proper salinity level had got to be wrong. With the info I have. your readings would indicate a salinity of 38PPT.
If I used the Hydrometer that I have (Standard Aquarium systems Seatest - Full Range specific gravity meter) and added salt till my Hydrometer read a density of 1.026 or a salinity of 35PPT I should be OK according to MFG. But according to The findings in this book my Temperature Conversion would be 1.040 and 40PPT
The book talks about (among others) the specific meter that I have and says that these dip and read Hydrometers are Calibrated at F75° and that we ourselves should also use distilled freshwater to calibrate our gauge's.
All in all I guess the salinity is estimated by the hydrometer of choice but the Temperature should not be taken lightly in determining the Salinity of your water and it appears the MFG should also give us the Info to correctly estimate our levels based on whatever temperature they calibrated their finished product at.
If I used the Hydrometer that I have (Standard Aquarium systems Seatest - Full Range specific gravity meter) and added salt till my Hydrometer read a density of 1.026 or a salinity of 35PPT I should be OK according to MFG. But according to The findings in this book my Temperature Conversion would be 1.040 and 40PPT
The book talks about (among others) the specific meter that I have and says that these dip and read Hydrometers are Calibrated at F75° and that we ourselves should also use distilled freshwater to calibrate our gauge's.
All in all I guess the salinity is estimated by the hydrometer of choice but the Temperature should not be taken lightly in determining the Salinity of your water and it appears the MFG should also give us the Info to correctly estimate our levels based on whatever temperature they calibrated their finished product at.
I had to keep track of the salinity as part of my job in the Navy. I have sailed all over the world and can say that the ranges were from 1.025-1.027(on average) depending on how closed or open the water body was and what other bodies of water were emptying into the salt laden body.
With that in mind. Mine is at 1.026.
With that in mind. Mine is at 1.026.
Jawbone,
I didn't mean to dismiss the effect of temperature at all. Temp does have an effect. I was referring to my readings using the T-M hydrometer calibrated at 77f. (I have checked it against distilled water and the TM is right on, while the Aquarium Systems plastic box reads about .001 low.) My target of 1.0255 is going to come out pretty close to 1.026 at 80f. The .0005 is my "fudge factor".
Robert Fenner says "A change of 10 degrees F plus or minus is accompanied by a specific gravity reading change of about 0.001." The Conscientious Marine Aquarist, page 97. This works out to "about" 1.02583 for me, using his values.
Interestingly, he went on to say: "Is this a big deal? In the grand scheme of things, no. A typical calibrated hydrometer is adjusted at 60 degrees F. Just know that if you want to keep your specific gravity at 1.025 at 80 degrees F, you will want a reading of 1.023 on the hydrometer."
The "Pros" seem to have a good time jousting with one another over the temperature and salinity issues.
http://www.reefs.org/library/article/reef_temperature.html
http://www.reefs.org/library/article/bingman_toonen.html
http://www.animalnetwork.com/fish2/aqfm/1997/nov/features/1/default.asp
http://www.animalnetwork.com/fish2/aqfm/1998/mar/features/1/default.asp
We, as amateurs are left to divine whom is correct or, if all or none are. I've ran my tank in the past from 77 up to 82~ and SG of 1.023 up to 1.0265 (corrected, of course
); and, using my simple tools, my tank seems to be healthiest setting the heaters for 80, allowing rise to no more than 81~82 during the day, with SG reading of 1.0255 at 80F.
Andy, I'll leave the blood-letting to Ernie!!
Dick
[ February 26, 2002: Message edited by: FishDaddy ]</p>
I didn't mean to dismiss the effect of temperature at all. Temp does have an effect. I was referring to my readings using the T-M hydrometer calibrated at 77f. (I have checked it against distilled water and the TM is right on, while the Aquarium Systems plastic box reads about .001 low.) My target of 1.0255 is going to come out pretty close to 1.026 at 80f. The .0005 is my "fudge factor".
Robert Fenner says "A change of 10 degrees F plus or minus is accompanied by a specific gravity reading change of about 0.001." The Conscientious Marine Aquarist, page 97. This works out to "about" 1.02583 for me, using his values.
Interestingly, he went on to say: "Is this a big deal? In the grand scheme of things, no. A typical calibrated hydrometer is adjusted at 60 degrees F. Just know that if you want to keep your specific gravity at 1.025 at 80 degrees F, you will want a reading of 1.023 on the hydrometer."
The "Pros" seem to have a good time jousting with one another over the temperature and salinity issues.
http://www.reefs.org/library/article/reef_temperature.html
http://www.reefs.org/library/article/bingman_toonen.html
http://www.animalnetwork.com/fish2/aqfm/1997/nov/features/1/default.asp
http://www.animalnetwork.com/fish2/aqfm/1998/mar/features/1/default.asp
We, as amateurs are left to divine whom is correct or, if all or none are. I've ran my tank in the past from 77 up to 82~ and SG of 1.023 up to 1.0265 (corrected, of course
Andy, I'll leave the blood-letting to Ernie!!
Dick
[ February 26, 2002: Message edited by: FishDaddy ]</p>
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