DSB... How Deep is too deep?

sbwing · 07/07/2007, 11:36 PM

I am setting up a 65 gal refugium tank to accompany my 40 gallon reef setup. It is a displayed refugium. The tank is a very deep hexagon tank and I want to add a very deep sandbed so I can reach the bottom of the tank. My question is how deep can I go before it can cause me problems? I wouldnt mind making it like 18"+ in depth possibly 2'. Can this cause problems?

TrueblueNY · 07/08/2007, 12:10 AM

they say there is no max but generally up to 12 inches for a DSB. over that doesnt help w/ anything like denitrification. if you make it really deep i dont know if whats alive in the sand will bourough that deep. the substrate in a healthy sand bed stays loose with oxygen and water moving though it brought about by the critters in the sand bed. i have seen deep beds that turn grey a couple inches below the surface, or harden up, and i dont know if that is healthy.

drummereef · 07/08/2007, 12:54 AM

sbwing,

To Reef Central

Young Frankenstein · 07/08/2007, 01:34 AM

I like DSBs and I setup one that's about 16" deep, there's no limit the deeper the better. The 1st inch is the surface, 2nd the oxygen zone and after 3rd the anaerobic zone without oxygen, that's the zone that eliminates nitrates.

sbwing · 07/08/2007, 04:16 AM

If I go too deep could I be inviting a hydrogen sulfide crash? This is what scares me. Is this a possibility?

Young Frankenstein · 07/08/2007, 05:05 AM

My DSB "bucket" is separate from my aquarium, fed by a pump, yes there's a lot of hydrogen sulfide in the first 3 months, it seems to decrease with time, but that's only if you mix any of the sand, in my case I have a drain that goes through the DSB. My main display DSB that's only 4" never gave me any problems because the fish and the critters only mix the surface.

wooden_reefer · 07/08/2007, 12:17 PM

Quote:

Originally posted by sbwing
If I go too deep could I be inviting a hydrogen sulfide crash? This is what scares me. Is this a possibility?

It doesn't take great depth for H2S to be a problem if there are food or fecal particles. Make sure that the water that goes into the DSB is as clean as possible. The minute among of food and exrement undergoes ammonification at the top part of the DSB.

The carbon food for denitrification is non-sulfur containing, non-protein.

kevin2000 · 07/08/2007, 12:27 PM

I doubt there is any benefit of going more than 5 inches in a DSB with fine substrate .. as far as too deep .. I doubt there is any downside so long as you have good water flow and don't use the extra depth as a sink for "crap".

07/07/2007, 11:36 PM	#1
sbwing Registered Member Join Date: Jul 2007 Posts: 2	DSB... How Deep is too deep? I am setting up a 65 gal refugium tank to accompany my 40 gallon reef setup. It is a displayed refugium. The tank is a very deep hexagon tank and I want to add a very deep sandbed so I can reach the bottom of the tank. My question is how deep can I go before it can cause me problems? I wouldnt mind making it like 18"+ in depth possibly 2'. Can this cause problems?

07/08/2007, 12:54 AM	#3
drummereef Team RC Member Join Date: Jul 2006 Location: STL Posts: 14,754	sbwing, *To Reef Central* __________________ -Brett 180g Marineland Starfire In-Wall 278 gallon system

07/08/2007, 12:10 AM	#2
TrueblueNY Registered Member Join Date: Mar 2006 Location: Upstate NY (Albany area) Posts: 22	they say there is no max but generally up to 12 inches for a DSB. over that doesnt help w/ anything like denitrification. if you make it really deep i dont know if whats alive in the sand will bourough that deep. the substrate in a healthy sand bed stays loose with oxygen and water moving though it brought about by the critters in the sand bed. i have seen deep beds that turn grey a couple inches below the surface, or harden up, and i dont know if that is healthy.

07/08/2007, 01:34 AM	#4
Young Frankenstein Moved On Join Date: Feb 2007 Location: Miami Florida. Posts: 3,842	I like DSBs and I setup one that's about 16" deep, there's no limit the deeper the better. The 1st inch is the surface, 2nd the oxygen zone and after 3rd the anaerobic zone without oxygen, that's the zone that eliminates nitrates.

07/08/2007, 04:16 AM	#5
sbwing Registered Member Join Date: Jul 2007 Posts: 2	If I go too deep could I be inviting a hydrogen sulfide crash? This is what scares me. Is this a possibility?

07/08/2007, 05:05 AM	#6
Young Frankenstein Moved On Join Date: Feb 2007 Location: Miami Florida. Posts: 3,842	My DSB "bucket" is separate from my aquarium, fed by a pump, yes there's a lot of hydrogen sulfide in the first 3 months, it seems to decrease with time, but that's only if you mix any of the sand, in my case I have a drain that goes through the DSB. My main display DSB that's only 4" never gave me any problems because the fish and the critters only mix the surface.

07/08/2007, 12:27 PM	#8
kevin2000 Registered Member Join Date: Jan 2004 Location: Portland, Oregon Posts: 3,805	I doubt there is any benefit of going more than 5 inches in a DSB with fine substrate .. as far as too deep .. I doubt there is any downside so long as you have good water flow and don't use the extra depth as a sink for "crap".