Question on Deep sand bed Tanks

[Randy-L]

I have reard some and read some about deep sand beds. does it have to be sand? Will crushed coral do? how fine or corse? How deep?

[mutts]

Crushed coral can be used but it can cause your nitrates to go up as the debris will get in and well not be able to get out. A DSB of 4 to 5 inches will create an anaerobic and aerobic levels that will help deal with the nitrates also. Also with sand you can get sand shifting invertebrates that will help keep you sand clean. With crushed coral they can’t get around and do their job. If you like the was crushed coral looks you can add some to your sand but we careful as it can cause pockets of air which isn’t good on your nitrates either. Hope this helped I’m sure someone will chime in with a better answear.

[PurpleAardvark]

Well put mutt's. I agree I really would not recomend the crushed coral on the top. I have had alot of people come in to the store lately who have done that and there nitrates have been testing anywhere from 50-100ppm.

[Dirt4dinner]

Randy,
I just added sand to my new tank a few days ago...don't even have rock in yet! I went with a DSB and was told by a VERY GOOD SOURCE at our local reef only store that fine sand is best for a DSB. I bought enough sand to go 6", but when I started adding sand, I realized that 5" was plenty! So, I have 5" and it looks great. I went with the finest stuff they had, basically like sugar. I was told that finer is better for DSB. Good luck.

[Reptoreef]

Both will work, however, it takes less depth of the fine over the course.

[RWalston]

The finer the sand the more surface area there is for bacteria to grow. The more bacteria the better the filtration. Deep sand beds are designed to give you aerobic and anaerobic zones. The aerobic zone is used to convert ammonia to nitrite to nitrate the same as your live rock does. The anaerobic zone converts nitrate to nitrogen gas (if working properly you will see pockets of gas bubbles in the sand. There have been a lot of discussions on deep sand beds crashing. IME I keep a shallow sand bed (3 inches) with more live rock and good skimming. The shallow bed gives you the benefit of an anaerobic zone along with the necessary population of biodiversity of live foods for fish and coral (pods). With good flow detritus will not settle on the sand bed but will be captured by your skimmer. To further help the sand sand shifting creatures help. I use snails and brittle stars for this. Many tanks are different and people’s husbandry practices are different. You need to find out what works for you. If you are using a sand bed and start to notice cyno blooms it is not necessary the sand but water movement and high pollutants in the water. I would not recommend crushed shell for a sand bed useless you are keeping fish such as jaw fish etc…, and then I would only use about a 10% ratio of crushed shell in the sand bed. As with this I am sure others will comment. Just figure out what you want and how to make it work for your system.

Rich

[Randy-L]

Okay - Thanks a lot for all the comnents. Now for the mother of all stupid questions. Sand of what material, sillica?

[PurpleAardvark]

Aragonite only. Sillica will lead to a hair bloom that make your tank look like it has a 70's afro from ****.

[RWalston]

What if you like green shag carpeting?

[mutts]

then give me your addy and i will ship you some hair algae... lol. i added a 20 lbs bag of shells into my tank and my nitrates are always at 20 and never go down from that so even that little bit caused some problems