help with salinity

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Hi its been day two of cycling my tank it is a 60L tank.

Yesterday I checked the salinity it was 1.025 today when I checked again its at 1.030. How do I get back to 1.025?

I'm not sure what I'm doing wrong as it is my first marine tank a total dummy right now

The tank just has water and sand. My aqua vetenarian said I must stop by tomorrow and pick up the live rock he has for me, I will also be taking some water for him to test himself.

So guys please throw me your views or experiences
 
:banghead::banghead::banghead::banghead::banghead:

Bud it is my frustration that newbies keep asking the same questions over and over.

Please search the forum on salinity and how to measure. As well as the difference between salinity that is measured ppt and specific gravity that is measured in mass to volume ratio.
 
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Pet peeve...

Yes.. But the grass route of the original posters issue. The swing in SG is most likely due to temperature and the misunderstanding of how to measure SG and how it relates to Salinity.

Now if you all would explain to the original poster how to use a hydrometer correctly then the cost of reefkeeping would come down. It seems that the flavour is "Refractometer" . Simply because the understanding of using a hydrometer is confusing to you all.
 
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Firstly, from the get go I bought a refractometer and therefore never had to learn how to measure SG and its relation to Salinity.

Secondly, you do not know if salt water was added as a large top up and would have increased salinity.

If the user said that fresh water was used to top up, then we would eliminate that and the next logical conclusion is the incorrect SG to salinity relation.
 
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Bud, the original poster was using a hydrometer with the references quoted. These variances are consistent to temperature changes and common issues with incorrect use of the hydrometer. Salinity does not change over night without changes to the water by means of additions to the water. However SG can change without additions to the water. Most commonly it is the temperature.

To quote remedies not understanding what the poster is referring to is irresponsible. Your suggestion could wipe out his tank simply because you do not understand this.

Please take time out to understand what I am referring to. It is no "pet peeve" I assure you.
 
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I have see you answer this type of question quite a few times and there is always slight frustration...hence the "pet peeve" comment.

But I would like to know how advising somebody to top up with fresh water to counter the evaporation is bad advice.
 
Welcome to the Forum!
Had all the salt dissolved before you measured the sg the first time?
The change may be due to a difference in temp wich can effect sg measurement, however a change from 1.025 to 1.030 is rather large so I don't think that is the cause.
Seeing as you don't have liverock, I presume you don't have livestock either? If so, then don't stress about fluctuating sg levels at this stage.
Will be interesting to see what reading the aqua veteran gets.
 
Guys, the role of this forum is to help newbies into the hobby, if every newbie signs up and asks the same question, so be it, that is the purpose of this forum, to HELP others, not to ridicule and belittle them because they are unsure of the correct way to do things. Most of us replying here have been in this hobby for many years, the newbies have been in the hobby for a week or two, it's NORMAL for them not to know certain things. That is why we encourage them to ask questions and state that "no question is a stupid question". This is EXACTLY why so many people are scared to post on the forum, because they get ripped to shreds when asking for help with simple issues.

Yesterday I checked the salinity it was 1.025 today when I checked again its at 1.030. How do I get back to 1.025?

I'm not sure what I'm doing wrong as it is my first marine tank a total dummy right now
Welcome to the forum, let's get back to original issue you had. :)

Certain hydrometers are notorious for being inaccurate with their readings being affected by various things depending on the type of hydrometer you are using, buying a refractometer is the best thing you can do. It will make life so much easier for you. I recommend not doing anything to the tank until you have gotten your refractometer, calibrated it and then tested your water for a couple of days. Let us know the readings and we can then help you from there. :)
 
What type of Hydrometer are you using? If you use the ones from Tropic marine they are very accurate and you never have to calibrate them. I, personally don't trust refractometers, (I have one in my draw that I never use, because it was always giving me the wrong readings) they can always get knocked about and they lose their calibration. A GOOD scientific hydrometer will always give you the best and most easiest way of reading your SG. You can then use a internet calculator to convert to salinity, here is the link;
Salinity Conversion Calculator
 
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What type of Hydrometer are you using? If you use the ones from Tropic marine they are very accurate and you never have to calibrate them. I, personally don't trust refractometers, (I have one in my draw that I never use, because it was always giving me the wrong readings) they can always get knocked about and they lose their calibration. A GOOD scientific hydrometer will always give you the best and most easiest way of reading your SG. You can then use a internet calculator to convert to salinity, here is the link;
Salinity Conversion Calculator


Agee with you Carlos! I'm also using a Decent hydrometer! (Lab quality) Got a Refractometer and after a couple of uses chucked it in the Drawer! In fact I don't know where it is at the moment!! LOL!!!!
 
Hi guys sorry for the late reply and sorry for causing a fued here, I have 12 years of experience with fresh water tanks and its my dream to have a saltwater tank so thank you guys for all the help

Today went to the aqua veternarian and took a sample of my water he tested and he also got the reading of 1.030. By the way I took my hydrometer along with me he used that and he also used one of his own equipment looked like a square 2cm thick filled water in it and the needle rises. Also 1.030. He then gave r.o water and told me do a 20% water change and let it run for 3 hours before I do another reading. So 3 hours late praying to god it works out next thing boom I have 1.025 shown on my hydrometer I excitedly ringed him and told him. He stopped by and did a reading himself, his also showed 1.025
he also did tests and wrote this down for me as I explained to him I joined a forum and will want to show you guys the readings

Salinity 1.025
Ph 8.5
Ammonia 0
Nitrate 0
Temp 26°c heater is set at 25°c

He said I must bring another sample to him tomorrow to do other parameter checks and I must pick up live rock tomorrow

I told him I need to buy a refractormeter from him he "laughed" and said .why do you need one? Your hydrometer, thermometer and fish food is all you will ever need the rest he can do for me free of charge including r.o water" I don't get this guy
 
No guys. The R42.29 hydrometer is very accurate. You just need to understand how to use it.

All these fancy bits of kit. Refractometers, density meters, mc meters etc are all very well and good. They have there place in the hobby. But not all can afford these hi end offerings.

My issue is that a newbie comes on the forum and states parameters. The newbie gets advice from members that have no clue how to read a, in this case, a hydrometer. Or the influences that can affect readings.

I will repeat this over and over like a stuck compact disk ? Salinity stability is the key to a successful reef tank. Understand this most basic parameter then the other parameters are a doodle to maintain. If your salinity is all over the place then your other parameter stability has on chance.
 
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Certain hydrometers are notorious for being inaccurate with their readings being affected by various things depending on the type of hydrometer you are using, buying a refractometer is the best thing you can do. :)

I have to disagree with this statement. The " inaccurate with their readings " is user related. I other words the user dose not understand how to use the instrument, or how to interperate the readings the instrument give. We refer to a hydrometer here. It is not the instrument that is inaccurate. It is the user that has no clue how to interpreting the readings

Refractometer is similar. Just because one gets a number from the readout. Does not necessarily meen that that is the SG or Salinity. One need to understand how to calibrate and what the instrument is indicating the its temperature range.

IMO the continued soliciting of members to purchase refractometers is driven by those with no clue how to read or calibrate a cheep hydrometer. :biggrin:
 
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To digress a lot. As a suggestion, primary and basic set up guidance might be a forum feature.

I am talking about. Starting an marine tank.
1) Understand how to make up and measure salt water.
2) filtration systems.......
3) cycling a tank
4) planing flow and circulation...
 
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