substrate - crushed or sand ? clean or not to clean?

[rwithey]

I have Carib Sea crushed coral for a substrate now, would I be better with sand? Should I remove the crushed coral or add sand to it?

I vaccum my substrate when I do a weekly water change, I know it removes the detris, but doens't remove the living stuff too? Should I vaccum less frequently or not at all? I see all kinds of life, mostly at night, in the substrate - I'd hate to suck it all out and not have it recover.

Also I was told to elevate my live rock off of the substrate, which I did with PVC pipe - is this really a good idea?

[Jimbo]

Hi I'm no expert on deep sand beds, but here's what I've heard and been told.

The crushed coral traps nutrients, because it is porus. Even if you vacuum it is the nutients are till stuck in it. You also remove critters. I could debate whether this is bad or good. But most people say it is bad. Mixing up the nutrients and critters seems to me to be a good thing from time to time (my 2 cents here). I certainly would like to here other opinions on this and justifications.

I used 4 inches or dolomite, got it cheap. and 1.5 inches of carib see sand. If you could figure out a way to crunch up your crushed coral into sand that would be cost effective. But I've yet thought of a way to do it, maybe some kind of grinder. If you have access to Southdown playsand from Home depot (oh your in washington Home Depot will not have it) that would probally be your best bet. A lot of people use silica based sand, but it could leach silica into the water, some say it does not some say it does, my LFS guy/chemist said he can prove it leaches into the water. Hopefully many others will comment on this since I'm new to DSB's.

Have a great day!

[HOT CORAL]

I have used crushed coral in the past, and although it is a good buffer, it can get "dead" spots.

Currently I have a Puka shell base, because I didnt plan on setting up a reef tank again, but low and behold it all started again when I saw a awesome piece of polyp rock. The shell base does allow a lot of critters....

I think a good refugium will take away the concerns of levels getting too high, with the crushed coral.

[OodleyBoodely]

For me, the advantages of a dsb are that it does drastically reduce nitrates and it does not have to be siphoned. I use nassarius snails and cucumbers to 'turn' the sand and I have never bought a 'critter' kit, but still have a variety of fauna living in my sand. I think the sand bed is really cool-looking. Only recently (after about a 1yr set up) I've noticed tiny brittle stars and tiny translucent worms, whereas befor, I'd only seen pods and bristleworms. This sand fauna all came from my lr and in addition to recycling nutrients in the tank, add more interest. I started my first reef tank using a scallop shell hash on the bottom. It very quickly became a grunge trap dispite siphoning, and, looked horrible, too. Fortunately, about that time I started reading about dsb and decided to try that, instead. I'm sure crushed coral would not be as bad as the shell hash I used, however, IMO, a dsb is much easier to maintain and looks good, too.

[HOT CORAL]

My next setup, coming soon, will have the DSB though because I like the look, although it will be the first time I have ever tried it

[rwithey]

How much sand should I use in a 50gal (same footprint as 55gal) and should it all be live or a mix? Any good sources to recommend either mail or the Portland/Seattle areas? ( I live 1/2 way between both )

Also should I remove by existing crushed coral or add on top?

[Jimbo]

Hi,

I used about 100 pounds of dolamite in my 40g and 40 pounds of araganite sand. The place is in beaverton that I got 2 88 pound bags for 30 and I payed 50 for the aragonite sand that I add to top it off. The dolamite grain size is about the size of a character on this display screen, but is not porus and packs down well. If you look in the phone book you should be able to find someone that has dolamite (sand and gravel) or nursary supplies.

Here's a pic of my tank



You can also buy it from these people
http://www.purearagonite.com/

Have a great day!

[rwithey]

Jimbo-

So, do you vaccum the sand - or just let the bugs do their work?

Rob

[Jimbo]

I just added the top layer and it took 3 days for things to clear up I don't want to stir the sand. You can get critters that will stir the sand for you. Microstars, cucumbers ect...

Check out these websites for critters.

http://www.garf.org/reefjanitors.html
http://www.ipsf.com/

I'm still new to this sandbed stuff also. I had about a 2 inch in my 55 with silica sand, I remember that I had more algea after adding the silica, this is not very scientific though. I also had plenty of critters, copods, spagetti worms, small feather dusters, sponges and the list goes on.

Have a great evening!

[rwithey]

I've got lots of those critters too, that's why I'm not sure if I should keep vaccuming. I am going to get some sand soon, but I don't know if I should throw out all the bugs by removing the crushed coral to replace with sand, or just pile the sand on top?

[Jimbo]

You could push the crushed coral to one side of the tank and add sand to the other side. Wait a month or two and remove the crushed coral.

have a great evening!

[rwithey]

That's not a bad idea - hadn't even considered it

Thanks!

[OodleyBoodely]

Also, if you only have a couple inches of CC, you could add enough fine sand over it to bring the level up to about 5-6". This way you do not have to get rid of it. If you add only about 1" of new sand at a time, and wait a week between additions, the sand critters will migrate to the surface. Adding some live sand to the top will help prevent a major algal cycle which you can expect anytime you change or mess with the substrate. When I added an inch of sterile sand to my existing sandbed I had a diatom bloom that lasted about a week. It wasn't too bad, though, and my cuc and lawnmower blenny enjoyed it.

[dwyatt]

Rwithey:

Wow, this is still a highly discussed topic. Most people agree that all CC is not a great idea for a reef tank. It tends to trap detritus and not keep the really small critters very happy. I changed my system over to a 4"dsb with good success. It has many advantages. IMHO what works best is a hybrid of the current concepts. I would keep some of the old crushed coral on the very bottom of the tank (about 1/2"). This will seed the tank and create a mini anerobic plenem for efficient de-nitrification. On top of that, I used 1 1/2"Caribsea seaflor reef sand which is a mix of grain sizes from small to medium. This will help lock in the CC and help keep it from shuffling to the top of the pile. On top of this, 2" of fine oolitic sugar sand offers a good habitat for the smaller organisms and looks good overall.

Definately don't vacuum the DSB. Good water circulation and lots of critters should keep the substrate looking good and healthy.

The PVC pedestals work great for me. I keep about a 1/4" gap between the sandbed and the bottom of my flat base rock. My brittle star moves freely under the rock and keeps it well groomed.

HTH,
Good luck

[rwithey]

Thanks guys!

I like the idea of leaving some in the bottom and gradually adding the sand on top- now I have some direction - thanks again for the tips.

Rob