How often do you vacume your sand bed?

How often do you vacuum your dsb if at all. Should I be doing this? and wont the sand just get vacuumed up?

I have noticed that my sand level is depleting. Is it OK to just install say 2 or three more inches on top of your sand bed? Of course I would be mixing it with the sand already there. I have about 3 inches in one of my tanks and its the carib sea special reef grade sand that is a little more course. I think I need more sand for it to do its job. I have noticed some nitrates in this tank and have adjusted my feeding schedule and this has helped.

Jay

 

It is quite normal to need to add sand on a regular basis.
I don't often vacuum the sandbed unless I have cyano or something.

I do stir my sandbed. A little bit each time I do a water change.

 

I vacuum my sand a little bit every time I do a water change, I don't go nuts but if I drain 15 or 20 gals I might vacuum for five, I like to go no longer than 3 weeks between changes

 

never! lol, i consider it to be a mini DSB, its like 4.5 in deep

 

I recommend doing it regularly. However, I'm going to try some SPS. SPS corals live in oligitrophic conditions. As a result, sandbeds, in spite of their de-Nitrification advantages, have the disadvantage of putting too many nutrients into a SPS tank. They also are a great hinderance at maintaining the proper flow necessary for SPS. As a result, this tank will be bare-bottom. Unfortunately, I like the looks of a sandbed but there's just no easy way around it. I wish I had the kind of money that Steve Weast has and could simply replace my sandbed every 3 months. (I love his tank http://www.oregonreef.com/sub_maintenance.htm ) If you go to that link, you can also follow his method of vacuuming. I did it differently. I bought a 5 micron filter sock for $6 , hung it in my sump, and used a python vacuum. That way I never lost any water but boy what ended up in the filter bag was GROSS.

I personally recommend vacuuming a sandbed often. If that is not possible, stirring is definately the next best thing. Unlike what Dr. Ron has proposed, a sandbed has a finite life. Doing these two steps will definately extend that life substantially. If you have a brand new sandbed, I would recommend vacuuming all the way to the bottom of 1/4 of your tank every week. (You will lose some anaerobic denitrifying bacteria during this process but that will only last for a day...that's why you only do a portion of your tank and not all of it). If you have an established sandbed, DO NOT GO ALL THE WAY TO THE BOTTOM. Sulphides can nuke your tank!!!! You could very well have a sulphide zone in the anaerobic area. Contrary to common belief, they don't always show as a grey line down near the bottom. The grey line is a result of Sulphide Oxidizing Bacteria reacting with Iron. If your tank doesn't have a lot of Iron sequestered in the sand, the grey line won't be there but the sulphides could be.

Here's the basics of my recommendation. I mentioned that sandbeds have a finite life....in other words, they eventually fill up. How long it takes it to fill up varies greatly from tank to tank. I.e. if you have a low bioload, feed sparingly, skim heavily, vacuum and/or stir often, are careful about Phosphate inputs, and have the proper number of worms, snails, in your bed for good bio-turbation, they can last for years and years and years. If you change one of the things in the sentence above, your sandbed will fill up faster.

HOW SANDBEDS WERE ORIGINALLY ADVERTISED...Put a whole bunch of sand into the bottom of the tank, put some sand stirrers into the sand, and don't touch it. All of the waste and nutrients will disappear because the bigger critters, will eat the bigger waste, poop it out, the next smaller critter will eat this smaller waste, and so on and so on until it finally goes, "poof" and disappears. Hmmm....think about that one for a second. If you think that this is possible as Dr. Ron INITALLY sold the sandbed, then you need to study the Laws of Thermodynamics. I made a smart alek comment once, "Sandbeds operate like wormholes and the excess nutrients and detritus are transported to a sister galaxy". Jerel (big-wig at the NOAA) actually PM'd me to see if he could put that saying in his signature on RC. I obviously was pleased that my sarcastic nature, which usually gets me into trouble, was finally put to good use.

HOW THEY REALLY WORK (SIMPLIFIED)...ALL living things contain Phosphates (P). As you know, Phosphates are algaes best friend You feed your fish an algae based product or an animal based product (or a combo of the two). Since the algae was once alive it contains P, since the animal used to make the food was once alive, it contains P. Since your fish ate it, it is now in the body of a living critter so it's called Organic Phosphates. Roughly 10% of the Phosphate and other nutrients in the food stay in the animal until it dies. Once it dies, all remaining P will become Inorganic Phosphate. The other 90% of the nutrients including P will fall to the sandbed as poop. Several possibilities will happen here. A critter will eat the poop, take it's 10%, poop out the rest for the next critter, who will take it's 10%, and so on and so on, or it will sit there until bacteria remove all of the nutrients from the poop. Either way, in the end, the smallest critter that will take that P is a bacterium....and then it will die too and release the P.

Ok...that's the nature side of things. Now we have to deal with the chemical side of things. P adsorbs to Calcium Carbonate. What is aragonite and live rock? It's Calcium Carbonate. Phosphate Adsorption That's good right? Now it is bound to something so algae and cyanobacteria can't get to it. I wish it was that simple. A bacterium measures its life in hours and not years. When it dies, the organic P becomes inorganic P and adsorbs the the sand. Unfortunately, bacteria don't have mouths and will create enzymes that will dissolve the P right off of the Calcium Carbonate sand. If you have a deep enough bed, low pH will cause this to happen without bacteria's help. Read "How Bacteria Eat".

Bacterial populations will grow based on housing and food. A sandbed contains tons of food and tons of housing. Unfortunately, our tanks are not the ocean....the bacteria cannot spread lengthwise nor downward as their waste is held in by 5 glass walls. What will happen over time is that the anaerobic portion of the sandbed, due to the restriction of their waste, will keep rising until it gets to the top of the sandbed. Once that happens, the P that dieing bacteria once released but was immediately re-adsorbed by the CaCO3 will now be going directly into the water column to be used by algae.

When someone tells me they have algae on their sand, I look at two options....their bed has "filled up" as described above or they don't have enough sand-stirrers to delay the inevitable as the waste is sitting right below the algae. Algae will lead you right to the source of P. Why do I recommend vacuuming? It's because you are removing sources of P that will cause your sand bed to fill up....thereby extending it's life. I also recommend that one continues to repopulate their sandbed of sand-stirrers on regular basis to help with bioturbation.


I want to make something VERY CLEAR. I'm not anti-DSB at all. I like the looks of them, I like to watch another minor ecosystem in the same tank with my corals and fish, I like to watch nassarious snails come out of the sand like, "Night of the Living Dead" when I feed my tank. What I don't like about them is that people have been told fallacies regarding them by a couple of people out to make a quick buck.

 

ya im not sure what to do, im going to get a 24 gal nano thats basically going to be for sps and i dont know whether to get a sand bed...that would limit my mobile inverts but...im not sure if its worth it for the circulation

 

Without want to be sarcastic, keep vacuuming until you have about 1 to 2 inches of sand left then stop.

Don't try to do this all at once, remove the sand over a long period and once you get it down to 1 inch then sell the vacumm on ebay

John

 

Hey I think I bought that vacumm.

 

That's OK. Once you have finished with it, get rid of the nuicance thing as you won't need one with a proper sand bed.

John

 

A couple days back I siphoned my sand a bit... I was amazed at the crap in there after a few months of neglect.. the side with the circulation dead spots - I sucked up red debris.. I don't know what it was but I was sure it probably wasn't the best thing to leave feastering in there... I say do some of it periodically... it can't be bad... that's for sure.. it's a closed system.. things build up...


matt