Marine Pure Instead of Live Rock?


New member
Returning to the hobby after several years. Would like to learn from anyone with direct experience setting up a natural live rock (Berlin) system using a relatively small amount of live rock in the display with Marine Pure media (only) in the sump? I have a new 90 gallon tank on its way and will use a 45 gallon sump/refugium from my previous build.

Assuming I use 35 to 50 lbs of cured live rock in my display, and if it will actually work, how much Marine Pure should I need (assuming block)? I have plenty of time to cycle the system to seed the new media.
I only learned of Marine Pure today and read somewhere on this forum that 1 four inch block was good for 100 gallon?

I appreciate your comments,


Skim junkie
I've used Marine Pure blocks before and they helped me keep my PO4 and NO3 down pretty good, but my corals always looked irritated when i used it. I use a combo of siporax and seachem matrix bio media in 2 linked reactors and my nitrates and PO4 have been easier for me to keep in check. I don't have a lot of LR in my 60 cube and prefer it that way because i can manage dead spots easier and keep good flow all around the rock scape. the reactors are more maintenance though. i give mine a good shaking periodically to release mulm and that stretches out my maintenance a bit longer.


Skim junkie
forgot to mention when i used marinepure blocks mine turned to mush when i tried moving them. not sure if they are different now but that's what made me make the change to siporax and matrix