Should I decouple my subs too?

Your best most cost-effective move will be Nobsound springs under the subs, and Townshend Podiums under your speakers. Read the reviews and comments, Gaia do not seem to be worth the huge price differential vs Nobsound, but Townshend is worth the huge price differential over Gaia. Also it just makes much less difference under subs, compared to mains. 

Not kidding about the manufacturers btw. Called a bunch of em. Total waste of time. And yes one did tell me I would kill myself. And no this is not the AI Millercarbon, I am still here even in spite of having committed the sacrilege of improving upon perfection.

Forgot to mention we have a suspended hard wood floor

Again Ron, nothing should be coupled to a suspended wooded floor, as it just becomes a "muddying sound-board" for whatever is coupled to it.

Cheers George

Thank you everyone for the advice. I really look forward to reading the daily posts. You all have taught me so much in the short amount of time I have been here. 

I have Gaia's under both of my subs (Tekton 4-10's) & they work wonderfully to decouple them from the floor. That stated, if I didn't already have the Gaia's, I would follow Noromance's advice above.  

I use a Sub Dude under my REL R305.and it made a huge difference in my set up.   Works well,  I put one under my Dad's sub and the bass is great and it doesnt rattle the rest of his house.   He kept playing movies too loud and it was keeping my mom up , so I went by one day with a Sub Dude.   He didnt even know I put it under,  i set his trims correctly and boomyness was gone.    Great product