How Often Do You Check Salinity?

[Ritteri&Bubbles]

I check my salinity when I do a water change, which ends up being every 6-8 months, but its always within spec as saltcreep in my tank is pretty much nonexistant.

 

[EmilyB]

Would a floating hydrometer (glass type) be a good reference to test a swing arm?

Thank you for you replies.

Marco

I believe they are temped for around 75 degrees. So you would have to translate to 80 or wherever you keep your tank.

 

[esmithiii]

Marco,

There is a difference between accuracy and precision. Have you used one yourself?

I also do not think that they are that accurate, possibly in a laboratory setting but not in reality. There are so many factors that can affect how accurate they are. I owned and used one for 18 months and I never felt I could trust the reading.

Any water turbulence and it doesn't work. They are difficult to read, and if they are not clean then the reading can be slightly off due to breaking the surface tension on the unit (the meniscus height would change if it is not clean). The meniscus was the length of a .001 tick mark. Do you read at the top of the meniscus, or at the bottom?

IMO very difficult to use accurately. I had to remove almost a gallon of water into a tall pitcher just to be able to use it.

 

[JeremyR]

Some floating hydrometers come with tubes to float them in. You really need to do that, rather than just floating it around in your aquarium to get a good reading. I'm not sure I see being clean as an issue.. not real hard to clean them, especially if you only use it when you are testing salinity, rather than just floating it all the time.

 

[Marcosreef]

Ernie,
I have the TM hydrometer and the SeaTest swing arm. I have always used the SeaTest, but after reading some posts people say that they are terribly inaccurate?

So I purchased the TM Hydrometer, and both readings were the same.

Do you read at the top of the meniscus, or at the bottom?

I read it at the top (unless this is wrong?).

You can use a graduated laboratory cylinder (I got one at the local photo darkroom store) which is slightly larger than the hydro itself, and as tall.

Unless both of my hydros are off, I have no way to tell :?

Regards, Marco

 

[esmithiii]

IMO, too difficult to use in an accurate manner. My experinece with the hydrometer has not been good. My refractometer is much more reliable, and easier to use. I have used the pinpoint monitor too, and it is easy to use but has a shorter life (IMO).

Ernie

 

[Marcosreef]

Thanks Ernie,
I will look into the Pinpoint Salinity Meter.

Marco

 

[Anonymous]

Just tested mine now. 1.0245. I think I tested last week sometime?

 

[dsb1829]

I have been pretty lax on checking this parameter. I voted on 1 week, but realistically I check it every 2-3 weeks. I am more prone to test on the short side as aposed to a month. For the most part it takes quite a while for this parameter to become out of whack. Only when I had 2-4gpd of evap on a 70g tank did this fluctuate at a rate for concern.

ttt...

 

[Anonymous]

i check mine weekly (with my seatest thingy) because i do weekly tiny water changes. i don't have a refractometer - but my critters always look happy so i don't worry.