Managing a Cryptic Fuge

[reefgeezer]

I need some advice please.

I've built a completely dark remote fuge. It is fed from the sump return section with about 100 GPH. Right now it is full of recently acid bathed and very dead Figi rock. I want to manage this fuge to supply bio-available nutrients, pods, and other coral feeding "stuff". Sooo... What organisms should I introduce into this fuge and how?

Oh... the fuge will feed a lighted display fuge that includes sand, sea grass, and some macroalgae. I'll have Dragonets and the like and some soft corals in it once the cryptic fuge matures. The display fuge will then feed the main tank, then back to the sump.

[Sinekal]

You could do nothing. Sponges and squirts should gravitate towards the area and grow on there own. Significant sponge growth can deplete some trace elements (I believe they may consume silicate, but you would want to confirm) so knowing them and potentially testing/dosing can help to maintain and grow a large population. I believe Steve tyree sells sponges to seed a cryptic fuge if you want to jump start the process.

If you want a significant pod population to make it to the display you may want the cryptic to feed into the sump or not keep dragonats in the fuge. They can consume a lot of pods and will keep the population lower as a result.

[atrox]

Why don't you want light in the fuge? A lot of the pods you are referring to eat algae. Kind of hard to grow algae without light.

[reefgeezer]

Originally Posted by atrox

Why don't you want light in the fuge? A lot of the pods you are referring to eat algae. Kind of hard to grow algae without light.

I have trouble keeping nutrients high enough to keep my SPS corals colored up. The problem is two-fold: 1) I don't have enough fish; and 2) the biodiversity in my system is so low so there is nothing producing food.

I am in the process of adding fish. That process is slow due to QT requirements. While I'm QT'ing fish, I'm also attempting to add biodiversity.

I have added a lighted 30 gallon display tank into the main system. It will have macroalgae and sea grass in it. It is not a fuge per se. It will also house soft corals, Dragonets, and other things. It will however serve the as a fuge as far as the macroalgae is concerned.

The dark fuge is a place to grow sponges and other organisms that do better in the dark. Some think these organisms can produce food & nutrients for SPS corals. That is my main goal for the fuge. It also is a great place to grow Pods which hopefully will allow me to keep Dragonets and such.

[Comedy Fish]

Following. You should post some pics.

[dtum]

Originally Posted by reefgeezer

The dark fuge is a place to grow sponges and other organisms that do better in the dark. Some think these organisms can produce food & nutrients for SPS corals. That is my main goal for the fuge. It also is a great place to grow Pods which hopefully will allow me to keep Dragonets and such.

John, have you considered a Deep Sand Bed instead? From what I understand it should also add the same type of nutrients back into the tank.

[reefgeezer]

Originally Posted by dtum

John, have you considered a Deep Sand Bed instead? From what I understand it should also add the same type of nutrients back into the tank.

I considered a DSB. I decided the cryptic fuge was better considering my goals. IMO even a well established DSB with lots of critters in it is better at lowering N than adding food. I already have a problem with N & P levels that are too low. That said, there will be some sand in the 30 gallon display tank. I haven't determined how deep yet. That may be determined by the needs of the Sea Grass.

I also considered plumbing the cryptic fuge separately to both display tanks in an effort to get more Pods to the SPS tank. Unfortunately, I think the flow through the fuge would have to be too high if I did so. There won't be much in the SPS tank that needs Pods anyway. Enough of the smaller particulate matter and nutrients I want for the SPS corals should make it through the 30.

I'll try to post some pictures soon. Hopefully my DIY-modified-recycled-ghetto system won't look too bad.

[Eric Boerner]

My last build had three cryptic zones:

Zone one was dark, filled with rock and sponges. Zero light helps sponges propagate faster.
Zone two was low-light, filled with a 10" DSB, clams, sea grass, and sand worms.
Zone three was fully lit, no rock or sand, just cheatomorph and pods.

What I was trying to accomplish was a more ecosystem approach to filtering. With that in mind, all of my return flow pushed through the zone one, then half that flow diverted to the DSB zone, and the other half diverted to the refugium zone. That allows max flow through the primary cryptic zone for large particulate matter removal, with lower flow rates through the DSB and refugium zones. At the time I was pushing 1200 GPH through zone one and roughly 500 GPH through the other two zones. I posted the set up and visuals back in 2004ish.

When I get the wet lab running again, I'll put together the same cryptic zone set up again. Rock/Sponges > DSB > Macro Algae.

[reefgeezer]

Originally Posted by Eric Boerner

My last build had three cryptic zones:

Zone one was dark, filled with rock and sponges. Zero light helps sponges propagate faster.
Zone two was low-light, filled with a 10" DSB, clams, sea grass, and sand worms.
Zone three was fully lit, no rock or sand, just cheatomorph and pods.

What I was trying to accomplish was a more ecosystem approach to filtering...

Thanks Eric. I'd appreciate your feedback as my project progresses. I chose to feed the dark fuge from the return section of the sump rather than from the DT overflow due to a fear of supplying too much gross organic matter to it. I am hoping this reduces the need for a lot of flow through the fuge. It is also not very big so there's can't be too much flow. The rock holding area is roughly 15" X 15" X 11", almost 11 gallons. I still haven't settled on a flow target but I was thinking 150 to 200 gph. The system as designed could handle up to about 500 gph.

[reefgeezer]

Here's the final flow design for the "cryptic" fuge. It's connected to the 75's sump. I'll try to post some pictures of the whole system tonight.

[reefgeezer]

OK... so I'm not so good at pictures, but I said I'd post some. Posting pics is not a strength either. Sorry.

[reefgeezer]

The tank that the fuge is hooked up to has no fish in it right now and all the rocks in the fuge and the tank have been recently acid bathed. There are a lot of tube worms in the tank's overflow, but otherwise there isn't much life that can migrate into the fuge.

I really don't want to pay the stupid amount of money the guys on the web want for a little bit of rubble rock and don't know anyone that might provide some. Any ideas?

[reefgeezer]

I'll bump this one time.

I siphoned some of the detritus and gunk from the bottom of my overflow and put it in the fuge, but I'm not sure it was anything but inorganic leftovers.

I've shut the skimmer off and thought about adding some vinegar to the fuge to get some bacterial mulm to grow in the rocks.

I thought about adding Pods, but I worry there's not enough food in the system yet to sustain them.

I also thought about buying a pound or so of live rock but I'm worried about hitchhikers transferring to the display tank.

I'd love to find a source for some pest free seed rock with sponges or sea squirts or something on it that aren't $100 (with shipping) for a tiny little bit of rubble rock.

[Eric Boerner]

John. As with everything else, the cryptic part is going to take some time to develop and mature. I wouldn't worry too much about your population dynamics in it just yet.

I'd snag some cheap "dry" rubble rock from somewhere. You don't really need that much. 10 lbs should be enough for your 15. You want small and compact rubble in there, about the size of golfballs. Or crush up the dry rock you have already.

Next... You need to find some sponges and squirts. If you have a close by friend with an older reef, they might be able to give you some squirts and sponges on the bottom of their live rock. If not, you'll need to order some online. Don't order rock, order just the sponges and squirts. Inland Aquatics were the only ones carrying a good supply of starters, but that was years ago.

Be careful when removing the squirts or sponges off the rock. Use a razor and tweezers and gently remove them without crushing them. They may not take in your cryptic fuge otherwise. Put those under your rubble rock and let the water flow through that for a few months. You should see a lot of little guys pop up within that amount of time.

[reefgeezer]

Originally Posted by Eric Boerner

John. As with everything else, the cryptic part is going to take some time to develop and mature. I wouldn't worry too much about your population dynamics in it just yet...I'd snag some cheap "dry" rubble rock from somewhere. Next... You need to find some sponges and squirts.

Thanks Eric, Sorry, I just saw your reply. I have added a couple of pounds of rubble rocks I had laying around and I'm looking for more. I did find green ball sponge and feather duster worms in my overflow so maybe there is some hope that life will migrate to the cryptic fuge eventually. I've also spoken with the people at Reeffarmers.com and they've offered a pretty good deal on some seed rock. I've also dropped some rubble rock into the overflow to see if I can grow some seed rock of my own.

By the way, does anyone know how I can move some of the ball sponges from my overflow to the cryptic fuge?

[Joel_155]

Curious about this. Interested in seeing your progress.

[reefgeezer]

So I decided to take a closer look at the corner overflow in my display tank. I knew it didn't get very much light. What I didn't realize was that it had become a small fuge over the years. Using a flashlight I discovered that there is quite a bit of life in there. Besides the ball sponges, there is also a light pink slimy looking sponge that coats an entire wall of the overflow. The Durso pipe has a black looking sponge on it. I can see two different feather duster worms, There's also a couple of things in there I can't identify.

I also ordered 5 lbs. of Garf Grunge Plus to add a little diversity and help speed the process. I know... patience is not my strong suit. It'll also add some more small rubble rock to the fuge as suggested by Eric.

[reefgeezer]

I added 5 lbs. of GARF Grunge Plus today. It consisted of some dime to quarter sized rubble, some small or broken shells, and a lot of fine sand. There was also a mat of fine Cheato in it about the size of a dollar bill. I put most of the grunge in the Cryptic Fuge. I also put some in the overflow and sprinkled a little on the rock in the DT. It really clouded the water but I'm sure it will settle out. I turned off the skimmer so any organic particulates might settle without being removed.

The piece of Cheato is hanging out in the sump for now. I'll light it for a while to keep it alive. I hope the life it might harbor will migrate into the system.

I was pretty pleased with the product and Sally at GARF was very helpful during the order process. I hope it's an inexpensive way to add some diversity to the fuge. I don't know exactly what was added though. The only downside I see is some very small pieces of Cheato that were in it. I'll have to pick them out if they settle in the DT before they start to grow.

[reefgeezer]

The water cleared a few hours after the GARF Grunge was added. Everything looks unaffected. The little bit of the Grunge I placed on the bottom of the DT looks really interesting. It'll be great when the new fuge is populated with the life in the Grunge and the stuff in my overflow.

The next step will be to introduce some Pods. I'm about 90 days from adding the first fish back into the system. I want to establish a good Pod population. I'll start adding a little phytoplankton along with the Pods.

[chicagoreefer20]

I salute you on your overly complicated yet awesome sounding set up!

[reefgeezer]

Originally Posted by chicagoreefer20

I salute you on your overly complicated yet awesome sounding set up!

Thanks... I think. It's really pretty simple. You should have seen the first few designs!

[Aquarist007]

When I upgraded 3 months ago I had two refugiums. I removed the macro algae one and kept this60 gal one with 200lbs live rock. Since carbon dosing all the macro algae has died off.
This one has a nice population of filter feeders and aptasia.
Do these require any light?

[reefgeezer]

Originally Posted by capn_hylinur

This one has a nice population of filter feeders and aptasia.
Do these require any light?

I have a bunch of those tube worms in the overflow box of my display tank. It doesn't get much light because there are no lights over that area and the overflow box is black on three sides. It is my understanding that they don't require light. I don't think light has any effect the Aptasia. I have some in the overflow box as well, but until I wiped them out they did just as well under bright LEDs.

Here's an interesting observation. As I said, my overflow box is black on three sides. It has one clear side. The sponges only grow on the sides that are black. The tube worms and Aptasia don't seem to be so picky but their distribution definitely favors the side with the clear pane. Maybe it's the little bit of indirect light that make them grow heavier there or maybe they just don't compete well with the sponges.

[Aquarist007]

Originally Posted by reefgeezer

I have a bunch of those tube worms in the overflow box of my display tank. It doesn't get much light because there are no lights over that area and the overflow box is black on three sides. It is my understanding that they don't require light. I don't think light has any effect the Aptasia. I have some in the overflow box as well, but until I wiped them out they did just as well under bright LEDs.

Here's an interesting observation. As I said, my overflow box is black on three sides. It has one clear side. The sponges only grow on the sides that are black. The tube worms and Aptasia don't seem to be so picky but their distribution definitely favors the side with the clear pane. Maybe it's the little bit of indirect light that make them grow heavier there or maybe they just don't compete well with the sponges.

Good observation. Tks John

[reefgeezer]

I took a look inside the fuge. There are now some sponges visible. I assume they came in with the GARF Grunge. There is also some organic coating on the rocks. Here's a picture...