DSB waterflow question?

[Marlin65]

I was going to put in a deep sand bed in my refugium, but on another web site I read a link from someone that seemed to have a lot of experience with DSB's and he said the water flow across the sand bed has to be the same as the tank flow you would have for sps.
In your Refugium your flow would be a lot less.

So just wondering what you all think about that I have never run a DSB.
I could put it in the main tank but am worried about the dart and 4 way blowing the sand all over the place. Or is that just a mather of adjusting the nozzles for that?

[coral reefer]

Yes, you want the flow of water in your refugium to be slower so that the beneficial water being cleaned(similar to the water in a skimmer) has more time! Plus the living organisms in your refugium don't require and are therefore hindered by the faster water flow!
As for a deep sand bed in your main tank, I employ the use of a fine grain sand, without any problems , as I just adjust and experiment with my powerheads to deter the sand from blowing around!

[Frizza]

I agree with coral_reefer.

However, if you're talking about a DSB where it's depth is just below the water surface then indeed you need a much higher flow, this will just stop to much detrius build up. The sole purpose of this is for denitrification. One method that I haven't actually tried myself but I would if I had more space is to install a remote DSB. This is plumbed in separately and therefore is easy to maintain.

Personally I would rather a refugium with say 3" of sand and all of the benefits that it gives. But if you have the space then why not try both methods, and if you need more flow on your DSB then just get a mini power head.

[Marlin65]

I am worried that if I put the DSB in my Fuge that it will starve of oxygen with the slow flow and turn anaerobic. (Black with rotten egg smell.)
In the main tank it would get enough flow, just worried about my sand as it will only be 60 gallons with a 3600 gallon an hour drive pump on a 4 way. This I would imagine will push a bit more than power heads. So I am not sure what will happen to my sand.

[Marlin65]

Well I have given it some more thought and I am still not too sure which way to go on the fuge.
Not sure that the power head in the fuge is what I want. Its a good idea but I don't think the pods and some of the other things I want to get for it will like that too much.
I think I will try just 1-1 1/2" of sand in the main tank.
Looks like I will have to do some more reading.

[Frizza]

Putting a sand bed of around 3" or so in your refugium should not cause you any problems at all, in fact I would say it is much better than say 1". You should benefit from NNR (due to anaerobic decay) and you will end up with plenty of life in your fuge and your sand bed will be full of activity.

Hopefully some others here will chip in for additional opinions/advice.

[Tangster]

A refugium is the only place I'd use a DSB.. As for oxygen deprivation that just allows for the anaerobic conditions needed to allow for Natural nitrate reduction to happen .. The plants will re oxygenate the water when lights are on. I remember when refugiums where simple. I use a refugium 1/10 the total size of the system its to support then flow 1/10 the fuges total water volume through the thing per hr. 100 gallon tan a 10 gallon refigium then 10 GPH more or less through it. This simple formula has Been working for me and many of my friends for many many yrs.

[Marlin65]

Thanks guys thats a bit of in site. I guess I will put a DSB in my fuge and just put enough in my main tank so I don't have a bare bottom.