Chemistry-wise, would adding this sand be a (temporary) problem?

[giants4pc]

I have a 156 main display with 75 sump. Plumbed in, I have a 90 gallon with a total volume of about 240 gallons. Right now, my 156 is a shallow sand bed (2-3"). My 90 is BB with about 50 lbs of LR and 3 fish that I don't want in my main display. I only have this right now for extra water volume.

After reading the latest issue of Coral Magazine, I am sold on the benefits of a DSB, especially as they have cast some light on many of the myths surrounding them. I want to add a 6" sandbed to my 90 and put some chaeto in there, essentially turning it into a large fuge. I think this will benefit my system a great deal.

My question is, would adding this sand cause a problem to the existing tank?

[Randy Holmes-Farley]

IME, I do not think the sand beds I had did anything good or bad so I removed them in a system overhaul a few years ago.

What type of sand do you plan to add?

[giants4pc]

IME, I do not think the sand beds I had did anything good or bad so I removed them in a system overhaul a few years ago.

What type of sand do you plan to add?

Interesting...and I certainly value your input. The article mentioned very small particle size so I was planning something sugar-sized. I did not have a particular brand in mind...something pretty standard. Now perhaps I won't waste my money.

[tmz]

I've also removed the deep sand beds in my system a couple of years ago ,except for one relatively small unlit refugia with rock on top ,which is still there and is not a problem but .I doubt it does much for denitrification though.. Adequate denitrification occurs without dsbs ,ime. For wrasses and other animals that need deep sand ,I build in pools of deeper sand fenced in with live rock, here and there.

Sugar fine oolictic sand is nice looking and provides lots of surface area for denitrifying bacteria. It's good for sand sifting animals like sea cucumbers and sand sifting gobies too. Iuse it in shallow beds in the display tanks. The downside is that it can blow around easily unlessyou adjust the flow patterns carefully. Fish and some siftres tendto spray it around on corals too.

I would be concerned about deepening a bed by laying new sand on top as the old sand and the organics in it and bund to it could become anoxic and create problems with sulfate reduction and hydrogen sulfide or other problems if the organics breakdown.