Hi I have buy a bag of gravel. It was cheap and the look was ok. Pacific gravel #2 made by Geosystem (Hagen). After a search on Hagen website, I found out that is crushed coral. I have done the test with the vinegar and it do alot of bubble so it mean that is aragonite. I dont know what to think about it... what should I do? Is it good to use or it will be a nitrate factory like some ppl say? I dont care to vacuum this gravel unless is bad to do it. It will be a fish only tank and maybe a low amount of base rock or live rock (don't know yet). Help me plz it will be my first SW tank. TYVM!!