Heres is a bit of the sticky for ya. It works just be careful and READ READ READ.
NOTE: This procedure can not be performed in an environment containing live rock, live sand or inverts [including crabs, corals, etc.] If you have a strictly Fish-Only setup, then the treatment can be done within the display, otherwise, you will need to treat infected fish in a quarantine/hospital tank.
You will need: Refractometer or a glass hydrometer calibrated to tank temperatures, pH buffers, a tank or quarantine area for the infected fish that is adequately filtered.
Hyposalinity is a procedure involving lowering the salinity from normal tank levels to 14 ppt (1.009 Specific Gravity) over the course of 48 hours. This is done by doing a series of small water changes using fresh dechlorinated water. During the procedure, pH must be closely monitored as pH tends to drop as water become less saline. Fish are maintained in hyposaline conditions for three weeks after all symptoms are gone. Again, accurate measuring is essential, and the standard swing arm hydrometers are not going to work. A refractometer or large glass lab grade hydrometer calibrated to tank temperatures is needed. Once the fish have been asymptotic for three weeks, the salinity is then raised back to display tank levels over the course of a week. Fish can not tolerate rapid increases in salinity. Leave the fish in quarantine at display tank levels for another week.
Your display will now have been fishless for at least four weeks, sufficient time to allow the parasite’s life cycle to be interrupted. ****** is an obligate parasite that requires a fish host. No fish=No host=No parasite. Ich is a fish-only parasite, it will not affect inverts.
Continue to monitor pH daily during the process and be prepared with buffers to address any pH problems. Also keep the water clean through proper filtration.
Refractometer Info by broomer5
Temperature does matter when using a refractometer with ATC Automatic Temperature Compensation. But in most every case ...... only when we calibrate it.
Refractometers used to measure salinity have an optical glass prizm inside.
As light enters the prizm, the light is bent.
This light is bent and projected through to the eyepiece, where we see the upper and lower color line, as it's projected through the scale graduations.
We place a sample of our tankwater on the glass prizm, flip down the light diffusing lid, and allow light to shine through the device.
The amount the light is bent, is a direct result of how much "stuff" is in the sample.
The stuff in this case is salt ( and all the other minerals and elements in our saltwater ).
When we look at pure water - the light is not bent much.
When we look at saltwater - the light is bent more.
The whole thing about using these types of refractometers, and getting good accurate results, is by following the calibration procedure.
When we calibrate it - we place a few drops of distilled water on the prizm. Then we MUST allow this distilled water to come to the same temperature of the refractometer. Normally this is 68 degrees F.
The device is built to be calibrated at 68 degrees F.
If you calibrate it with distilled water at any other temperature - then you will introduce error into the calibration procedure.
Basically - you'd be calibrating it to a different temperature than it was designed for. This would give you false readings every time you used it from that point on.r />
It's the room temperature that the refractometer is kept in, and used in, that is important when you calibrate it with distilled water.
The drops of distilled water will become whatever temperature the unit is. In other words - you place a few drops of distilled water on the prizm that is already at 68 F.
The drops will either warm up to or cool down to 68 F rather quickly.
Then, after a short period of time, you zero the device by turning the screw to align the scale's 1.00 SG and 0.0 ppt to line up with the two color boundary line. We shift the scale when we calibrate it.
As long as you do this calibration at 68 F, then you're good to go.
Afterwards - should the room temperature that you keep and use your refractometer stay within the 50 to 86 degrees F range, then the ATC auto temp compensation will adjust the reading for you. It's the room temperature ( refractometer temperature ) not the tankwater temperature that is temperature compensated and corrected.
The ATC is just another piece of glass ( prizm ) inside the unit that bends the light backdown. It sort of bends the light in the opposite direction as the main prizm. Not very much - just a little.
This feature "corrects" the image as the scale is viewed through the eyepiece. But again .... this auto temp compensation will only correct the reading we see if the refractometer and sample are at a temperature between 50 to 86 F.
Both salinity ppt and specific gravity "readings" are affected by temperature when using a refractometer. They have to be - they are on the same scale.
The salinity of the tankwater is not greatly affected by temperature, within the ranges we keep our aquariums. That tankwater contains so many parts per thousand of salt no matter what the temperature.
It's when we try to measure it, or convert this ppt into the specific gravity scale ...... that's when temperature comes into play.
Salinity in PPT or parts per thousand is just that.
Seawater is normally around 35 parts per thousand.
If you had 3500 pounds of saltwater, and boiled off all the water, you'd be left with 35 pounds of salts.
Specific gravity is not the same at all.
Specific gravity is a comparison of the saltwater to that of pure water.
Pure water having a specific gravity of 1.000
If you take 1 milliliter of pure water ( 1 cubic centimeter or cc ) and weigh it ...... it would weigh exactly 1.000 grams at 68 F.
If you take 1 milliliter of saltwater ( 1 cubic centimeter or cc ) and weigh it ..... it would weigh more than 1.000 grams at 68 F.
Why would it weigh more ? Because there's more stuff in it than just water. Theres' salt in there too, along with the pure water.
So it's going to weigh a little more. It's going to weigh 1.0XX
XX being the weight of the salt in that little cubic centimeter box.
How much more it weighs ? It all depends.
It depends on the actual amount of salt and minerals dissolved in the sample .... and it depends on the temperature. Now we're talking about density. How much stuff is dissolved in the water.
And the density of a given volume of liquid changes as the temperature changes.
If you're using a refractometer with ATC - and calibrate it right - and stay within the 50 to 86 F range, then you need not worry.
If you're using a refractometer without ATC - you still must calibrate it right ....... but you'll need a chart to correct the reading to the temperature of the sample.
If you are using either a floating or swing arm hydrometer - then you MUST know what temperature it has been calibrated at ( designed at ) and what the temperature of your tankwater is at the time you measure.
Then you look at a chart that plots temperature vs specific gravity - and determine the actual salinity in ppt.
Also realize that there are refractometers used to measure other liquids as well .... and some of them are designed to be calibrated/used at temperatures other than 68 F
