The Sandbed-Shaken- Not Stirred?
I've created a DSB in my marine tank.
<Good for you! An excellent technique to reduce or eliminate nitrate continuously and naturally!>
I wonder if I should add any sand shifting (if so which ones? I need some reef safe ones) organisms.
<Personally, I am against the heavy "stirring" of sand, by both the aquarist and sand-dwelling animals. I like to disturb the sand as little as possible. IMO, It's okay to stir the very top layers (no deeper than 1/2"-3/4" or so, just to keep the sand from clumping, but it may not really be necessary if the system is well-maintained. If you are inclined to use "sand-sifting" creatures, I'd limit your "crew" to a few brittle stars. They do a great job at scavenging uneaten food and detritus, and do not overly disturb beneficial processes occurring in the sand bed.>
But then, if they shift sand will that not provide oxygen to the lower layers of sand, so no anaerobic bacteria will grow and therefore no nitrate reduction will occur?
Thank you.
<Well, the argument for as little disturbance to the sand bed as possible holds well here! Over-zealous "maintenance" practices can interrupt the very processes that you are trying so hard to foster! Read a lot more on sand beds in Anthony and Bob's new "Reef Invertebrates" book! God luck and enjoy your system! Regards, Scott F>>

Kole Tang and ich problems - Answer to Vacuuming Sandy Substrata de Marina
Also how would I gravel vacuum a fine sand substrate? I have the Oolite Aragalive so if I vacuum the bottom the sand comes out also. 
<I didn't know you had a fine sand bed. You probably should add (if you don't have) some sand stirring critters. I guess the AquaClear 110 would probably work to a degree, but with a 4" sand bed in the filter I'm thinking that the water flow through the sand won't keep up with the 400+gph pump on the filter.  James (Salty Dog)>
>>James, I happen to have more experience vacuuming sandy substrates than I care to, and if you'd like to place an addendum to this, please let's.  These substrates CAN be vacuumed quite effectively, but it requires a VERY LONG (and I do mean very long) vacuum tube.  An equally outrageously long section of flexible tubing is also necessary, this length seems to help "drive" or power the siphon better.  When I worked at the Long Beach Aquarium of the Pacific, one of my regular "chores" (ha! As if it could actually be called a chore!) was to feed and care for the baby bamboo sharks in the coral lab (public display area). They are grown out on sandy substrate, in what for all intents and purposes is essentially a large cat-litter pan.  Filtration and water changes are, of course, quite important, but more so with these little ones. They left quite a bit of uneaten food (even with hand feeding), so I had to vacuum the sand very regularly. The tube was about 3' (three feet) long, with about a 2" diameter. That, along with keeping a kink in the hose (hand-controlled) allowed me good control. There were those who tried to use ball valves in the line, but you just can't get the same control as when you "hand kink" it.  Marina<<

Hawk/Centropyge compatibility, safeness of milk jugs 8/19/05
Hi, I have a couple of non-related questions please.  I have a 75 gallon saltwater tank currently with 1 large flame hawk and 2 false perculas.
I purchased a coral beauty angel a couple of months ago and everything seemed fine until about a week ago.  I noticed its fins were ragged and it quit eating.  I had noticed the hawk chasing the angel several times while feeding.  The angel died yesterday.  Is it possible that if I bought another angel this might not happen again?  I know nothing is guaranteed.
<Will very likely re-occur>
Also, I keep my water to compensate for evaporation in plastic milk jugs.  Should I change out the jugs after a while.  I have read about water getting bacteria in it from plastics breaking down, but didn't know if there was anything to worry about with fish.  thanks for your help, James
<Don't think there is any reason to change, toss these containers. Bob Fenner>