We purchased some SoundTrap ST600s and have had an uncharacteristically high number of issues. Most recently, one flooded and another had a battery blow. We aren't sure whether the latter was caused by a small amount of water or... something else? Has anyone else had issues with these instruments and what have you done to reduce hardware loss?

  • 1
    Seconding knowing a colleague that just had one flood.
    – selene
    Jul 5 at 14:02

6 Answers 6


We have also experienced some issues with the water-tight seal of these units. We are experimenting with different o-ring sizes to see if it helps, but I will have to report back on that.

In the mean time, we have started to add PTFE sealing tape around the outside of the seal, and then secure that with electrical tape. This can help re-enforce the water-tight seal.


We also experienced repeated flooding of SoundTrap hydrophones until we started using waterproof tape around the seal. We then wrap the waterproof tape with electric tape. It's an inexpensive product I bought in the plumbing section of a local hardware store.

  • Did the waterproof tape leave any residue (sticky goo) after you removed it? I'd be curious what kind you used!!!
    – Shannon
    Aug 2 at 23:12
  • 1
    Hi Shannon! There is a minor amount of sticky goo left behind when I remove the tape, I scrub it off easily with dish soap and a kitchen sponge before opening the hydrophone. Here is a link to the tape I've been using! I also wrap electric tape over the waterproof tape to make sure the edges don't come up. amazon.com/dp/… Aug 17 at 20:46

I know of another two examples of flooding this instrument recently, so it hints to a design problem with the O-rings; try write John Atkins at Oceaninstruments.

  • Have also had units in my working group flood recently. Something about it being confusing that there was an o-ring outline in the bottom of the instrument, but this only sometimes had an o-ring actually in it (in same model of 2 instruments, as received directly from manufacturer)
    – Chloe
    Jul 5 at 13:12
  • Thanks, we are in talks with them. In the meantime debating whether or not to go back to our older versions. Jul 6 at 15:36

We have deployed a number ST600s without issue thus far. However, in terms of battery issues, it would be prudent to note that counterfeit batteries are a concern that should try to be mitigated by buying from trusted sources. As far as flooding goes, besides inspecting, cleaning, and lubricating o-rings, wrapping the seals of the housing with electrical tape should help, as previously mentioned, as well as keep the o-rings cleaner after deployments.


I have not used SoundTrap myself, but I usually use custom-made hardware made by our lab (down to 900 m). I can only confirm that our engineers and technicians pay a lot of attention when closing pressure houses, attaching connectors, etc. Proper handling is extremely important. So not all is with the manufacturer; the final responsibility is with customer, sorry.

And yes, sourcing batteries these days is becoming increasingly difficult.

And finally, I would not be surprised, if someone complains about bad microSD cards. The market is full of bad products.

  • 2
    I know that someone has developed a method to test Li Batteries before deployment. I hope to learn that process and will share. It was developed by an electrical engineer so it seems like it will be useful to spot bad batteries. Yes, memory cards are also a problem. Spend the extra money and buy from trusted sources.
    – TJ Rowell
    Jul 5 at 19:33
  • 1
    We are in talks with the manufacturer now. I would argue that if this many people are having issues with the same product globally, there is likely some issue with the product itself. That being said, there is always room for user error. Jul 6 at 6:01

We recently lost 4 (!!) ST640 (multi-channel version of the ST600) and the problem in our case appears to have been due to over-tightening of the locking screw.

As per the user guide the locking screw should be turned until 'snug' against the housing ie no force required.

If the locking screw is tightened too tight-- it may cause the housing to deform. John Atkins tested this on one of his instruments, and by really cranking on it (to the point the locking screw is about to strip), he got the housing to deform out-of-round by 0.1mm, which is probably just about enough to cause the o-ring to leak.

So, short story is - don't over tighten the locking screw. He's pretty sure this caused our leaks.

Side lesson learned: Do not over-lubricate your o-rings. In our troubleshooting search we came across this great information from Seabird on taking care of o-rings (see link at bottom to videos).

  • O.M.G. Just wow. I'm so sorry for that. Sep 8 at 21:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.