Just re - did my entire tank- I have a 5 gallon bucket full of super porus live rock- this is malesian island rock- not dense stuff- I used it in my sump- great stuff- but I decided to not have it taking up space. Need to sell quick- since it's in a bucket with water. You won't be disappointed. Just text for fastest reply. Located in El cajon. 619-922-8664 - Stephen