I'm sitting on the edge of the rockpool on this one☺.
As some like you Mark know I am quite new to iNat wrt submissions but like Tony I often take underwater pics in rockpools, even shallow sandpools.(But so far most of my recent pposts have been from SCUBA dives in open water).
I have,for the few posts I've already done involving tidepools (mostly one particular intertidal Aboriginal heritage fish trap tide pool which is big enough to warrant snorkeling around in and even at low tide still has small channel connecting it to open sea) included brief notes saying (e.g.) " At 1 m depth in tidepool v snorkel".
However I can see merit in your suggestion Tony.
I myself would probably still want to maximise the potential future research data value of my rockpool posts by including extra detail e.g. "...with tide out and heavy cloud cover".
But if you Tony mean you point a dry (land use only) camera from above very calm windless surface of pools to take photos of critters living below the surface - which obviously can give very good results when conditions are right,and whole books used to be produced relying only on such photos- then I see your point!

There is now a "rockpool" option. Most of my photos are taken with a compact underwater camera, which gives rather better results than taking photos from above. And usually when the tide is out, otherwise there is too much turbulence (and silt etc) from the surf (But sometimes the water is too shallow even for a compact camera).

@markmcg I have been using this observation field for a while now. I have two suggestions. With the growth of microfishing, I think it would be a good idea to add it as an option so that it can be tracked separately from standard angling. Secondly, I have recently had a few people ask questions about the field due to the name. I am wondering if it could be renamed to something more concise like 'Fish Observation Method' for example. Thank you!