adding calcium nitrates for color of corals question

[SaltEverywhere]

Thanks Randy, both for this reply and for all the amazing contributions to this hobby. I just wasn't sure if we are all using the $9 for 4oz high grade product or if everyone has discovered some cheap hydroponic calcium carbonate that is safe and reliable. I'll grab the higher purity item then.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks! You don't need to use much, typically.