I need to get rid of my 5 yr old sand/crushed coral bed and replace it with 100% southdown. Are there any detrimental effects that this can have if I do it all at once? I was thinking of doing this all in one day. I also have a 18" eel and a couple of other fish I need to remove and I've tried almost everything to get the eel out and would like to rearrange some of the rock anyway, maybe swap/take some out, etc... My nitrates are through the roof and I can't get them much below 100. Yes, that's not a typo, I said 100! LMK what you think.....