Refugium Substrate Poll

[jman785]

What substrate for a Refugium?

1. CaribSea Mineral Mud

2. Kent Biosediment

[jman785]

bump

[BobWeiss]

What about just plain old Southdown?

[SaltwaterSensei]

I would use the mud because thats what I'm using now, but I'm not using MM I'm using the mud that billsreef.com sells its a whole lot cheaper then MM. But I've only had his mud so I wouldn't know how it compares to MM.

[DT's_Reef]

I used 5" of Kent Biosediment for my refugium and it's worked great. It's 7 months old now and no problems. Lots of pods, ministars, worms, tons of macro.

[apophis924]

I use seachem's bio matrix. It is a porous inert substrate a little larger than gravel size. It is a LOT like chips of volcanic pumus that does not float. It is very similar to live rock in the fact that it is porous all the way thru. Thus it provides numerous growth sites for denitro bacteria. It also makes provides excellent contact points for macro roots to attacht to and it has enough space for pods and shrimp larvea to move around it.
It will not compact like sand
will not blow around if water flow is too high.
Pods can be siphioned off and transfered to the main tank without worry of picking up substrate.

[jman785]

What about just plain old Southdown?

Southdown lacks the minerals and trace elements available in the mineral mud and biosediment products...

- Jared

[BobWeiss]

I know what you mean by Southdown having no minerals but what I meant was how come you didn't ask about southdown in the poll just to see how many people are using what. Just a thought.

[Mako]

5" of SD is what I use in my 55g fuge and it works rather well. No problems growing the heck out of Macros and the life is just everywhere.

[jman785]

Well I might have to add a little southdown to my mixture of mud...and I'm definently going to try that biomatrix stuff...

- Jared

[BobWeiss]

The southdown is doing pretty good in my tank. I have it my fuge and its like 5" deep. Plus the price is UNBEATABLE!

[Plantbrain]

You can doctor up the SD by adding laterite/iron filings etc and then some vacuumed mulm from an established marine sand bed. Instant tank substrate with bacteria, organic matter, critters, traces.

Vacuum the established tank and let the water settle in the bucket for 5 min.
Pour off the clear water and save the mulm on the bottom. Get a liter per sqft to add to the tank. Mix well(+ iron source) in the bottom half of the DSB.

Flourite is similar to the Boimatrix but with iron/smaller grain sizes. Each grain is a micro environment with aerobic and anaerobic regions. I've just started using it in the macro tank. Since macro's are not particularly rooty, mixing of the two layers(white aragonite on top) is not such a problem.

Regards,
Tom Barr

[jman785]

Tom,

I've recently been trying some similar things, I put a layer of aragonite down first, then a 2" bed of mud, then another inch or two aragonite. I never thought about adding mulm to a tank like that, I'm going to have to try that when starting a new tank. I just happen to have some laterite sitting right next to me...but I thought the metals in laterite weren't good for saltwater aquariums?

- Jared

[Plantbrain]

The metals are fine. Bacteria and the other critters in the more reductive region/layer ease the assimilation of Fe. You can use rust. All the iron additives have a chelator, some are stronger than other etc, ETDA is stronger(Binds the Fe tighter, takes more energy to remove it from the chelator) than say gluconate(Common in vitamins). A few grasses, like corn (Not seagrasses) have trouble with strong chelators(Grass also have the extrenally excreated sidraphores to bring in Fe to the plant), but most every marine plant/alga will take the Fe in a two step process. Externally on the cells surface: Fe3+Chelator or bound to something, like -OH or ETDA, then Fe3+ =>Fe2+ and the Chelator or -OH is left outside the cell and the Fe2+ is taken inside the plant/alga.

Plants and algae have many ways to get at the Fe in the water. So do bacteria. They don't need a lot but they need a semi constant supply.
If you fear laterite, I know a number of folks that have used it over the years, you can try flourite or oxyn sand(Has some alkalinity buffering).


The mulm is great, it's everything you need for starting up any tank.
Think about what a 2 year old DBS has that a new one doesn't.

Yes, it takes a little while for it settle in, but essentially it's the only thing missing from a old mature substrate vs a new one.

Not sure why folks use cycling products. We did not have these many years ago. We did not need them then, nor do folks today. Mulm does the trick just fine. It's fresh, it's free, it's precisely what's in an established DBS.

You can vary the content or this however you so desire. Richer might want a deeper/finer cap over it etc.

There are many different substrates for Refugiums but they are all pretty similar and less critical than folks like to claim. Most have aragonite/laterite or some iron rich material, organic material, a little, not too much etc.
They generally help get the plants/algae through leaner times when the nutrient level in the tank get too low to support good macro growth etc. When there's not enough nutrients for the macro's, you get the smaller nuisance algae generally.

I get the mulm from the Keys, that's precisely what the plants like and where the plants grow. Bring a bucket and come on down. I'm heading down after the 4th of July for 4 days.

Regards,
Tom Barr

[jman785]

So you vacuum real ocean mulm? heh sweet...I'm thinking about doign that, the 5th is my birthday :) I'm about to go get certified this week I do believe...

- Jared

[Plantbrain]

Since you live here, there's no excuse:)
Most of the sediment is old Halimeda opuntia anyway. I've hits spots 3-4ft deep. Not vacuum needed, just a shovel.

Regards,
Tom Barr

[Evergreen]

I use a 6.5 inch bed of southdown in the refuge, I have macro growing like nuts including planted halimeda. The tank is only 3 months old and is loaded with worms, pods etc. (among some unmentionables LOL)

[jackson6745]

I have also been using SD in my refugium in my 3 month old reef and I have pods, worms, and mini stars everywhere----and my macros grow very fast. Why waste the extra money on the mudd???

[rotterdamcowboy]

Hey Plantbrain,

Wish I had come across this thread sooner - I recently just siphoned out approx 2-3 liters of crushed coral from the bottom of my 200 liter tank. I've setup a Refuge with something kinda like Southdown, and also used the same sand in my main tank as well.

From the Crushed Coral, I used my wifes strainer (she loved that idea!) to seperate the CC from all the "life" (pods, worms, etc.) as I wanted to put this back in my main tank & refuge.

I couldn't get all the life seperated from I think was really fluidy mud type substance. When I seperated this "mud" from the clear water (once it all had settled), I had about 3-4 cups of this "mud". Not able to seperate all the life from this mud, and concerned that this mud might be more like a "nutrient bomb" if I put it all back in the tank, I settled on a comprimise. I figured the 40-50 kilograms of LR I had would already contain enough "life" to thoroughly populate the tank with more pods, worms, seastars, etc. - I opted to about a cup of the "mud" back in the refuge. This also was a hedging of my bet, as it's easier to break down my 45 liter refuge than my whole tank to clean it out if I had ended up making a mistake I needed to back out of.

I didn't mix in this "mud" with the sand - it's just kinda loosely laying on the top of the sand, but the gentle currents in the refuge have gradually cleared off some parts of the sand & collected the "mud" in other parts of the refuge.

I also have about 2 handfuls of Caulerpa Prolifera growing in the tank, and some thing that I think *might* be spaghetti macro, but not quite sure.
http://reefcentral.com/gallery/data/500/28037PICT0342.jpg

So what do you think? Is this type of "mud" I gathered, kinda like the mulm you are talking about seeding refuges with?

Or did I make a grave mistake?

BTW, I checked my water a couple of days after all this, and my Nitrates have shot up to above 50ppm, but my Nitrites & Ammon & everything else appears to be perfect. I'm mixing 30 liters up now to do a water change to take care Nitrates, as I expect this is from all the "nutrients" I stired back into the water changing the CC out for sand.

-> Kev