Newbie Salifert Test kit help

[Morg591]

Ok.. perhaps im an iddiot... but Im having trouble understanding how to use some of my test kits... I got the Nitrite and Ammonia down ... but the Carbonate Hardness/Alkalinity and Calcium tests are what I dont understand. I just purchased some Kent Marine Kalkwasser Mix and Super Buffer dKH and want to understand the tests before I jump in... Also .. any special recomendations on adding this stuff to my tank for the first time? ... Thanks in advance for any help ..

 

[BBReefkeeper]

The Salifert test kits do have a lot of parts with them, but simply read the directions and you should be ok. If you didn't get them with the kit let us know. As far as the Kalk mix, you might try pickeling lime from the grocery store. Mrs. Waggs or Ball will work fine, they cost under $2 for twice as much. When you mix up your Kalk don't just pour it in, you will screw up your PH and have problems. Drip it at whatever your evaporation rate is. When I did that it was about one drip per second. Good luck and try doing some searches for the topics. You might get some more detailed info.
See Ya
Bryan

 

[AnotherGoldenTeapot]

Well here's how I run the Salifert Alkalinity test.

1. Measure 4ml of water into the test vial.

2. Add 2 drops of the indicator solution (the blue/green stuff).

3. Fill the syringe half way, put the yellow nib on and then empty the syringe back into the bottle.

4. Fill the syringe to the 1ml mark (without step 3 I find I can't get it to fill to 1ml with the nib on). Step 3 is not in the instructions, but I think it should be

The solution in the test vial at this stage is blue.

Repeat the following:

5. Add one drip of the solution in the syringe to the test vial.

6. Swirl for a few seconds.

7. If the solution is still blue then repeat from step 5.

8. Eventually the solution turns pink/red and stays that way.

9. Look at how much solution is left in the syringe and then look up that amount on the test kit instructions to see what the alkalinty is.

The solution first turns pink/red it will probably turn back to blue if you keep swirling. You're not finished until it stays pink/red even after swirling for at least 30 seconds.

Once you know approximately what the alkalinty in your tank is you can just add solution from the syringe upto near (but before) the amount you think you need and then start from step 5. Of course if you have added too much and the solution has gone pink then you need to start again.

The calcium test is similar but the color change is harder to spot. The method I use to detect the color change is to look away while I am swirling the solution then look back. I find I can more easily tell what color I am looking at that way. If you keep looking at the solution while swirling the gradual color change that occurs can fool me into thinking I've hit then end point when in fact I have not.

Another trick is to assume you have reached the end point of the titration (the fancy word for what you're doing) and, look at the reading (in case you really have finished) and then add one more drip to the test vial. If the color changes profoundly then you hadn't finished.

It's critical that you do these tests using natural light. It's no good using reef lighting as there's not enough red in reef lighting light to be able to spot the color change accuaretly. A similar problem occurs under household light bulbs that don't have enough blue - wait until it's daylight is the best bet.

 

[Ph]

On the Salifert kit one thing to note: The instructions say that the test is calibrated for the air bubble you always get in the syringe. I have seen a problem with this. When you draw the solution up always look at the size of the bubble. It should always be 1ml if it is more than that shoot the solution back into the bottle and do it again. On occasion I have seen the air bubble as large as 2ml, this can goof a test.


On the Ca test the color change can be brutal for people who are color impared. When I do the test my wife has to tell me when its gone all blue. They state clear blue, but I have never really seen it go all that clear. Now for the big question do you take the reading when it turns purple or wait till its all blue?


HTH

Ph

[ January 15, 2002: Message edited by: Ph ]</p>

 

[AnotherGoldenTeapot]

You're right - ignore the air bubble and fill the syringe with fluid to the 1ml point.

 

[danmhippo]

The air must be in the syringe to make sure the 1ml solution you draw are all emptied out as 1ml in its entirity.

 

[AnotherGoldenTeapot]

The only reason for having some air is that that a meniscus forms at the top of the liquid allowing you to more accuartely fill to 1ml.

There's nothing forcing you to empty the syringe below the 0ml mark (which is possible - and important that you don't on tests where you have to add more than 1ml) so you can add "precisely" add 1ml.

It's almost impossible to end up with no air in the syringe because the plunger does not go right to the end of the syringe. You're bound to get at least a 0.1ml bubble in the syringe.

Make sure the liquid goes to the 1ml mark and ignore where the plunger is was what I was getting at.

 

[Lunchbucket]

if you just fill it so the plunger bottom (side toward the tip, bottom when you are filling it) is right at the 1ml mark it is ok. yeah you have air in there but it takes up the same amount of room as the liquid would. you are not (hopefully) going to empty all the way to the air. so it is useless to have the air pocket filled...it is just a space filler so you get to 1ml. if the plunger is filled till it hits the 1ml mark..just add till it changes color and read where the plunger stoped not where the liquid is...just the same as a full syringe but the air takes up some of the room. it won't throw it off

later
Lunchbucket