5 year old two-part. To use or not to use?

[stevie1493]

Title sums it up. I have Bionic two-part mixed new in 2016 that's about 1/2 full. I don't see any precipitation after shaking and letting everything settle. Would you use it?

 

Edit: Everything I've read is telling me as long as nothing precipitates it should have an unlimited shelf life. I'm leaning towards using it, but am still interested in others' opinions.

Edited October 30, 2021 by stevie1493

[NoOneLikesADryTang]

How much money do you have in corals, versus what does a new jug cost?
 

Me? I’d throw it out, and get a new one. While it may be totally fine, it wouldn’t be worth it to me risk thousands of dollars in corals to try and save a few bucks

[mcarroll]

Precipitation should only occur if there's been contamination...such as some alk (bicarbonate) getting into your calcium chloride solution.  (This makes chalk, which is chemically inert.)

 

BUT...

 

If you're thinking how sometimes there're precipitation solids in the ESV (only larger sizes), then that type of "precipitation" can (and needs to be) re-dissolved before usage.  This is actually a part of the instructions on the bottle.  From ESV's non-linkable FAQ at https://www.esvaquarium.com:

Quote

It is normal for the B-Ionic Alkalinity component to precipitate chemicals if exposed to temperatures below 60 degrees Fahrenheit. For Concentrate, we recommend diluting your product with RO/DI water, keeping it in a warm room, and intermittently mix the product until (48-72 hrs average) all chemicals go into solution. For product packaged in 5 gallon buckets, look down through the spout to make sure all chemicals in the bottom have been dissolved. In order to accelerate the process, you can submerge the bottle in warm water (120-130 deg F). Just be sure to put the bottle in a bag before you submerge it, because our labels are not waterproof. For the ready to use alkalinity component, simply mix intermittently while storing in a warm room to ensure all chemicals are dissolved. The solution should be completely dissolved before use. Check the bottom of the container, and if you see any undissolved material, it needs more time and/or heat.

 

This type could be re-dissolved again if it happened to you....but you'd have to lose a lot of water to evaporation for that to happen.  I doubt you have any precipitate.  (Mostly because you didn't mention it.  😉)

 

There's no reason not to use it.  It doesn't "expire" in any way.

[stevie1493]

1 hour ago, NoOneLikesADryTang said:

How much money do you have in corals, versus what does a new jug cost?

My instinct is with you, but I am a penny pincher at heart... I know your question may be rhetorical, but around $600 in coral vs $40 in two-part.

 

5 minutes ago, mcarroll said:

There's no reason not to use it.  It doesn't "expire" in any way.

Thanks for feedback and link! This is pretty consistent with what I read both on old forum posts and info from ESV. I don't have a Cal test kit and I don't dose things I don't test for. Unless someone convinces me otherwise I'm going to use it as soon as I get a Cal test kit...ideally this week.