Yes, quite common in micro teaching labs. Our staining trays have a drain hole and tube that you can connect some tubing to and run into a waste container. I have attached some photos too for your edification.

They are from the year of the flood and I had trouble finding any for sale – this is the closest I could find like ours:

https://www.mopec.com/product/slide-staining-tray-kit-bg015/?_gl=1*etmjwk*_up*MQ..*_gs*MQ..&gclid=CjwKCAjwhZDUBhBGEiwAbi5bjoUzkb7kkh_0WCn5nK6IEKmno3yIxsO1UBZlLn6qhi9EZg52cH1i1xoCh_kQAvD_BwE&gbraid=0AAAAAD-om2KYBKXUDtljIYDOu_dNfN1DZHere     Look for staining trays, maybe you’ll have better luck that I.

You have to maintain the waste containers closed when not in use, you can’t forget to take the cap off the waste container and put the tubing into the waste container, otherwise you have a spill. >From the photos you can see we use 5 gallon DOT rated containers that can direct ship when full. The techs help design these staining stations.

Our techs do a good job of keeping the area clean, minimizing splashes, and managing the hazardous waste.

Good Luck,

James

Good afternoon Kayla,

Hope all is well.  I have spoken with many lab managers and microbiology faculty regarding this, and  this is a very common problem in academic institution microbiology labs.  We also had this same problem with splash back during gram stain collection at our institution.  In response to this I created a protocol in which we no longer have splash back on our students, walls, or lab benches.  This is done by not using distilled water to rinse the trays, but to pour as much of the stain as possible into a properly labeled waste collection container and then completely wiping the small amount of excess stain out of the gram stain collection tray with paper towels.  The paper towels are then discarded, and the dry staining tray is put away.  I have included pictures that we have in our labs that show students how this should be done. Also, I would greatly advise AGAINST doing any waste collection in any sinks at any time.  Hope this helps, and please feel free to contact me if you have any questions or concerns.

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> on behalf of Kayla Johnson (she/her) <Kayla.L.Johnson**At_Symbol_Here**UVM.EDU>
Sent: Wednesday, August 12, 2026 10:59 AM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Subject: [DCHAS-L] Gram Stain Rinsing Collection | Teaching Lab

Hello,

We got a question from a TA coordinator about collecting large amounts of Gram stain and the best way to do rinsing to collect it as waste without high chances of splash back. 

One option that was suggested was to use bins in the sink to then transfer to a waste container or directly rinse Gram stain into the waste container. The issue that by using a squirt bottle or sink into the waste container, the container sits high enough that it would create splash back onto the students. 

The second option was not as feasible; it was to have the plumbing disconnected and have the bin placed directly under the drain. Seemed like the best option until we discovered we cannot have the plumbing disconnected in this space. 

Would anyone have any good ideas?

Thank you,

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