Sand Bed Replacement

[greasemonkey]

I have been thinking of removing my dsb from my 20gal and setting it up in the fuge I am currently working on. Does anyone have Ideas on the best way to go about this? I am sure I will have to remove all my rock and livestock, but I feel people here can tell me something to keep me from messing something up.

I will be using new sand and hopfully some starter sand from another member.

This is in a 20 gal with a minibow 5 fuge and 10 gal sump.

Thanks ahead of time.

[greasemonkey]

So I should try rubble in the fuge? What should I put on the bottom of the tank?

[JimD]

Yeah, like mine, going on four years. A sandbed, like anything else, needs to be mantained to work efficiantly over the long haul. However, Im in agreement with ole Josh that tour tank is way too small for working sandbed, use rock rubble.

[Ram_Puppy]

I think rubble would be great in your fuge, a place to breed pods!

[greasemonkey]

Very good. I will make plans for rubble rock.

[GaryP]

I have a few questions for those advocating giving up their sand bed. What takes the place of the DSB for nitrate reduction? Sure, there will be some in the deep pores of the LR.

My other question is whether there isn't a proportional effectiveness of a DSB in a small tank. Its logical that the DSB won't process as much nitrate in a 20 gal. as it will in a 125 gal. but then not as much is produced in a 20 gal. either.

I think the real problem is that most 20 gal. owners aren't willing to give up the necessary tank volume to get a true DSB. A 4 inch DSB will take up about 1/3 the volume of a 20 gal. That's about 6 gal. of the total volume. Everything I have read about DSBs say that you need at least 4 inch to get the proper anoxic conditions foe the bacteria that do nitrate reduction to N2.

Am I missing something here? Please feel free to shoot holes in my logic.

Gary

[GaryP]

Greasemonkey,

I know that Aquatic Warehouse (and possibly other LSF) offer rubble for sale at a reduced price. They get it in the boxes of LR they recieve but don't sell it and it piles up. I know I boutght some at Texas Tropical a long time ago, but they sold it to me at the same price as regular LR.

Gary

[Richard]

I've never been completely sold on the Shimeck style DSB. In fact, even he suggested that it might be necessary to tear down the tank every 5 years. That said, I have never really liked the look of bare bottom and some of my favorite fish require sandbeds. Although I do believe you can get denitrification from sufficient amounts of quality liverock.

Luckily, some recent experiments showed that denitrification rates were the same from a 1 1/2 - 2" bed of sugarsize sand as they were from a DSB.

[GaryP]

Richard,

Thanks for the input. I was hoping you would chime in. I guess the key to a thinner sand bed is the sugar fine. That makes sense since it packs tigher and would have less oxgeneated flow. I guess that's a disadvatage too.

What is your opinion of operating a plenum? I know some people that I respect that swear by them.

Gary

[Richard]

Gary, people I respect very much swear by plenums but I have not found them to be any more beneficial. In fact, pulling out a couple of plenums that I had in some of the store tanks I can only think that they are an eventual nutrient sink with all the muck that was built up underneath them. And these tanks never even had fish in them.
For now, I'm very optimistic that my tribase carbon "DSB" will remove nitrate and phosphate. I'm getting ready to setup an experiment to see if it works or not. Do you know of a source of phosphate and nitrate that I can manually add to the tank. I'd like to do the experiment without any livestock, liverock, or sandbed. Just manually add phosphates/nitrates and see what happens.

Oh, here's the article I was telling you about. Your one of the few people who would actually find this interesting. LOL
http://www.protein.bio.msu.ru/biokhimiya/contents/v65/pdf/bcm_0341.pdf

[GaryP]

Richard,

An easy source of phosphate and nitrate. Ever consider fertilizer? Try some MiracleGro (15-30-15). Its liquid and easy added. Its 15% nitrate & 15% phosphate. The 30 is for potassium and shouldn't be an issue. If you looked around you could probably find some that doesn't contain potassium but I don't think it will be an issue since its a natural part of seawater and you won't be adding enough to be a major issue.

Gary

[don-n-sa]

I know that the salt/water or ( saline) mixture that companies inject into the chicken we eat contains phosphates. They do this for flavor and to add weight since we buy by the pound. :shock:

Oh if anyone thinks that it is gross then try chicken that is not injected and you will no the meaning of dry and flavorless. ;)

[Richard]

Should I use white meat or dark meat. LOL

[GaryP]

Richard,

I am looking forward to hearing the results of your carbon bed experiments. Please plan on giving a talk at a meeting on it after you get some results. Pretty please?

One question, how are you going to innoculate the bed with bacteria?

Gary

[Ram_Puppy]

Ricahrd, i have been fascinated with your carbon DSB for a while, but aren't you worried about it leaching back into the water once it reaches saturation? or are you hoping that the porus nature will offer superior surface area for colonization, and so on?

I also didn't realize that a sugar fine DSB did not need to be so thick, I may have some extra southdown in that case. (no, don't anyone hit me up for it... stuff is like gold! :) )

[GaryP]

Steve,

Colonization as well as chemical adsorption is the idea behind a carbon DSB. I have read some things that suggest not replacing the carbon as often, or only partially replacing it, about 25% at a time. The porous nature of carbon makes it a very good media for bacterial colonization. It has a huge amount of surface area for colonization. Sort of like supercharged bioballs. The difference between carbon and bioballs is that it allows for condition of both anoxic (very low oxygen) and aerobic bacteria while bioballs are strictly aerobic (high oxygen).

The carbon absorbs the organics and then acts as a media for bacterial degradation of the organics. Carbon is like a giant sponge and the internal areas allow for the anoxic conditions needed for growth of nitrate reducing bacteria like exist in a DSB.

Gary

[Ram_Puppy]

so, this isn't a fire and forget for a few years type DSB, portions of it are periodically replaced? And since it's bio-active, and contains anoxic zones, there really isn't anything to release back into the water other than nitrogen gas which should outgas into the room right? does the bacteria keep the carbon from ever reaching saturation? also, in a normal DSB you get active colonization of all types of critters, and you keep it stirred with snails and other guys, I am guessing the colonization sill occurs, but no large creatures are used for maintenance.

[Richard]

Steve, According to the manufacter of tribase carbon it will eventually leach but by the time that happens it doesn't matter because the bacterial removal of phosphate/nitrate will be very efficient. I had it on my 46 gallon for a year now and I clean the glass every 2 months (just scraping off coralline). It has no skimmer and gets a 5 gallon water change every 4-6 weeks, so something is working.
The tribase carbon is extremely porous and provides huge surface area for bacteria and one of the carbons used is supposed to be available to bacteria (something talked about in the link I posted to GAry). As it says on the bag "IT SIZZLES" :lol: . It actually takes a day or two of soaking it before all the air comes out of it and then it will sink. The manufacturer claims to be able to do nitrate/phosphate removal aerobically with the carbon in a hang on or canister filter but the formula for how much carbon is (water volume * .1667 = lbs of carbon to use) so for a 50 gallon tank that would have to be one hell of a hang on filter. He says the carbon will need to be replaced every 5 years.

Gary - I was going to run the tank for 6 - 8 weeks with some liverock then remove the LR and add phosphate & nitrate to some measurable level and see if the levels go to zero.

[GaryP]

Richard,

Keep good records on the data you get and I will graph it out for you to show how fast the nitrate/phosphate is depleted. It would be great to use a regular DSB/LR systems as an experimental control as a comparison.

Can you get us a deal on a bulk order of the tri-base carbon? I was thinking of trying to get something like that organized for a bag of Hydrocarbon. It came up #1 in Farley's test of various carbons. Maybe a 50# bag?

http://web.archive.org/web/20010211125931/www.animalnetwork.com/fish2/aqfm/1998/june/features/1/default.asp
http://web.archive.org/web/20010211125618/www.animalnetwork.com/fish2/aqfm/1998/may/features/1/default.asp


Gary

[Richard]

It would be great to use a regular DSB/LR systems as an experimental control as a comparison


I'm using a 62 gallon tank that will eventually be a mangrove/seahorse tank (or maybe a mangrove/dragon moray tank or maybe mangrove/... tank). If you'll buy me a matching setup I'll be happy to run them side by side for comparison :D .

[Ram_Puppy]

wow, sounds like the holy grail of carbon. Are you guys carrying this yet richard?

[Richard]

We've been carrying it for a couple years. Very good stuff and a little cheaper per lb than marineland.

Gary - we looked at the 50 lb bags for store use but his pricing is pretty much the same per lb as on the 5 lb bags.

[Ram_Puppy]

I am going to grab some next time I am in Richard, I have been using cheap crap for a while, and I think it contributed to some of my problems.