crushed coral begins to dissolve , acting as a buffer . The aragonite content  increases the effect . We put it in filter media bags and 

hang them in the water flow near our sponge filters .You can put  it inside filters or simply add to the substrate . You should do your 

research as how best to use it in your setup . Repackaged from bulk in plain bags .

 You will get a 200g bag of the crushed coral with  a zip-up media bag .

The media bags are approximately 15cm x 20cm . Sent the same day if ordered by 11 am . 

Thanks for looking !