Sera Test Kit (major error found )

[mordibv]

Not sure if anyone is aware but thought I would share.
I picked up some Sera tests kits a while back . I have used them before with good results . These were to replace the Tropic Marin Kits i have .
I ran out of the TM and did a few tests with the Sera . I kept getting a low DKH and low Ca levels .
As a result of this I kept adjusting the dosing pumps . I added some CaCl to the tank 1/3 the dosage per the calculator to raise the levels to NSW parameters. It immediatley precipitated out of solution .
This gave me a HMM moment .
I left the dosing pumps and set them back as they were .
I then out of curiosity took a syringe and measured out 5 ml of tank water per directions .
WOW .
It read 7 ml on the test tube label . I then measured to the 5ml mark with the test tube and took out the test water with the syringe .
It measured out as 3 ml .
Both my calcium and dkh sera beakers measured the same . 5 ml is truly 3 ml .
I could have seriously screwed my tank up .
The tests come out correctly if I measure 5 ml or use the 7 ml mark for the test sample water .

Here is a pic .
Water sample on the left is drawn out by the syringe in the middle came out to 5 ml .
Water sample to the right came out as 3 ml by the syringe .
Proly not worth complaining to Sera about it . I talked to a buddy in NC and his test tube bottle is off the same way .
In a nut shell if I went by the test tube ml mark I got a test of 5 dkh .
If I added 5 ml and tested I got a result of 8 dkh .
The calcium is saturated atm . PHEW .

 

[WoodRiverTroutBum]

That is something they should definitely be aware of. I would call them to let them know at the very least.

 

[mordibv]

I guess I will do that . It really made me a lil crazy trying to figure out why the dkh and calcium dropped so low . I have been chasing numbers for two weeks .

 

[Andy V]

I have yet to find a test tube where the marks were correct. I always use the syringe to measure. The good news is that the Sera kits are accurate in my experience. The same results as Elos.

 

[RadReefer]

All test kits I've dealt with that are already marked are never accurate. This is why elos doesn't put lines on their vials, it's manufacturer error. I'm sure there are plenty of people out there that are dosing based on inaccurate values. Always use a syringe to draw up your sample water.

 

[mordibv]

All I got from Sera was a canned response and instructions how to use the kit . I am so used to Salifert and TM water sample draw with a syringe . The thought never crossed my mind the graduations on the cylinder were wrong . Talked to the pet store an alk kit came from . He verified the same issue with several vials .
Think about it , since the kits are economical , noobs would buy them in a hearbeat . They also would not know any better . I know when I first got started I loved to adjust this and that . Newcomers would proly be the same way . @ Andyvalk I agree the tests are fairly accurate when you have drawn a correct 5 ml sample . Just my GI Joe lesson to myself for the day .