Ocean floor basing

[MechaDinosaur]

I'm doing a project where I'm making everything underwater themed, I'm wanting to do a basing style that matches it but that's mass producible since it has to go across an entire army. I'm going to include some props, make seaweed, include coral and just a general oceany theme to it but I'm not sure how to do ocean floor colour wise. Since the army is Torquise and rusty brown/orange it's going to contrast it's self pretty heavily right out the gates, which is part of the idea. The issue is what colour would make it look oceany without it becoming a case of the base being deep ocean while the models aren't tinted the same rich blues so they don't fit with the overall theme.

I'd really appreciate some suggestions. I don't want the bases to just use props, it needs to be oceany in it's own rights rather than having to tell someone it's underwater because it's got a crab and a treasure chest.

 

[Dragonsreach]

From Documentaries I've seen most ocean floor varies between pale silty sand to very pale muddy debris.
However all seem very smooth surfaces.

Having said that you really need to do google images or speak to experienced divers.

 

[MechaDinosaur]

I've done a lot of research but I've come to similar conclusions to yourself. If I do it pale sands it's going to look like they're on a beach rather than under the ocean, which is the problem I'm having. How do you imply ocean rather than summer holiday?

 

[Dragonsreach]

Paint light ripples on the floor.

EDIT: Sorry that reads quite sharp. My fault for posting late at night when I'm tired.

If you can look at images of underwater where light ripples are evident on the sea bed emulating that might be the way to go.
Failing that I'd suggest giving the shadows a Turquoise / Blue cast.