Large Macro Refugiums and Detritus

[griseum]

After a lot of in-depth research & reading, trial & error (and more error), I've incorporated Bare-Bottom, large square footage refugiums to my system for the cultivation of different macroalgaes, for nutrient export and as a side benefit, some tang-food.

So as time passed, I discovered which Macro's did best under different lighting, with the eventual goal to have the best nutrient exporters that proliferated under the lowest watt-consuming lighting fixtures. The watt-consumption was of importance because my particular experience has shown that certain alga do best with a constant photo-period for most of the week, interrupted by 12 to 24 hours of darkness and respiration. This avoids sporulation in some genera, etc.

The catch is, with tanks with a large footprint, and lots and lots of algae growth, comes lots of detritus, as a byproduct. Another cause for detritus accumulation is heavy, heavy snail populations and their byproduct.... SNAIL POO. And i mean lots of snail poo. Most of the snails that inhabit these tanks are, of course, herbivores that occasionally scavenge for other items. One species of snail, a Megastrea spp., Ive witnessed devouring tube worms/polychaetes.

Make this long story a little shorter, I've been on a search for the best of the best Detritus-eating Detritivores (or as I've also seen them called, Detrivores). Basically sh*t-eating, benthic, opportunistic scavengers.

And yes, of course, I manually remove and siphon as much dirt as i can from these tanks on an obsessive/compulsive basis. This is all in an effort to lower the extremely high nutrient levels in this closed system with a total volume of 2200-2500 gallons.

Throughout the years in the hobby, one of my utmost favorite aspects of Marine Aquariums is the bio-diversity. I strive to create a Natural Reef environment through biology, assisted by some technology. I do use a BEAST of a, Precision Marine Bullet-XL Dual Beckett 60" protein skimmer and some really good Reeflo water pumps. But, otherwise, I would gladly choose a natural solution to a problem over a technological solution on any occasion. So if anybody would like to Critique(sp?), criticize or relate to this too-long of a thread, please do.

I don't even know if there's anyone out there who, like me, enjoys seeing a Bristle worm in their live rock, slithering about? Or a population boom of Flatworms sliding on the front glass of a fuge, and a wrasse getting fatter by the minute dining on them. Just a few of the many things i like, that most people spend lots of time trying to eliminate.

 

[emict326]

I had a similar set up, although a lot smaller 200gal water column and had the same problem. I was never able to find a good natural solution that worked long term. I will be interested in seeing what people say or if they have any new ideas. Oh and yes I liked having worms everywhere, I think more just because the freaked out my wife.

 

[griseum]

Great! Im hoping to hear some new thoughts and suggestions too!

Those worms can be scary the first few times you encounter them.

Wouldn't want to meet a big one in a dark alley!
lol

 

[griseum]

How are Centropyge spp. Compatible with ornamental shrimp? How about black brittle stars, well fed, in a macro fuge tank with those same Lysmata spp. Shrimp?
Anybody have experience with those combos, whether good or bad?

 

[Epicreefer]

If your trying to minimize detritus but add biodiversity stay away from the sea hare, I added one to my bare bottom 60g tank and the amount of detritus went up by 5-10x. I've heard there are other sea slugs that are good detrivores though, most of them seem to be yellow for some reason...

 

[Reefin' Dude]

why not just use an empty settling tank and siphon out the detritus instead of trying to hide or find something to eat the various types of detritus? an increase in biomass means an increase in total nutrients. goes against the BB method of nutrient export.

G~

 

[griseum]

I w9uld like to further this discussion when I few minutes to respond properly. Im looking to learn various other ideas to further perfect my ssystes trophic balance.

 

[LouH]

why not just use an empty settling tank and siphon out the detritus instead of trying to hide or find something to eat the various types of detritus? an increase in biomass means an increase in total nutrients. goes against the BB method of nutrient export.

G~

Reefin' Dude, why don't friends let friends use refugiums?

I apologize if you've been asked this question 100 times, but I see your posts routinely, and I need to know.

Lou

 

[Reefin' Dude]

because they are nothing more than a septic tank. they just collect wastes. they do not actually export or do anything really useful with nutrients. they in fact increase the total nutrients of the system. people focus on testing the water without actually looking at the system as a whole. the test kits only give a very narrow view of what is going on in the tank. they only test for inorganic nutrients. they completely miss the organically bound nutrients. they are still there even though we can not test for them. the live sump (hobby refugium) just provides a place for the nutrients to settle, not a bad thing, but then nobody actually cleans them out. the point of them is to collect waste, then allow that waste to rot, to then grow algae or some other organism, to then "export" it. the problem is that that organisms is also producing waste. algae is not very efficient at using up phosphates. it produces a fair amount of waste phosphates (organic) while it is living. again it goes back to what we are testing for. it may seem that the phosphate level of the system is low, but in fact, if the algae is even growing shows that the phosphate levels are not really that low. depending on the trophic level one is trying to emulate, this can or can not be detrimental to the rest of the system.

i like to use settling tanks for nutrient control. either leaving the sump completely empty except for equipment, or adding a specialized conical tank to the system in order to collect the detritus in a single spot that is easily siphoned every week during water changes. the more detritus you are able to see, the more likely you are going to get to it and the more stable you can maintain the system. nutrients in controlled biomass is a lot of potential nutrient release at a moments notice is something were to change in the system. anything from a change in temp, a change in feeding, or even the tipping point of nutrient absorption in the system. they can all cause a chain reaction in the living biomass.

that is why friends to not let friends use refugium.

G~

 

[LouH]

Yes, that will do nicely. Thank you for taking the time.

On the subject of clarification, we have a primary wastewater treatment plant where I work, and we use both sharp angled cone clarifiers as well as large diameter but more shallow clairifiers. In both designs you deliver the infeed stream to a central tube which diverts the flow to the bottom of the vessel. Both designs use overflow rings around the rim of the vessel to allow clarified water to be seperated from the hign TSS water. The last vessel in the system before the outfall to the public wastewater treatment facility is a 1.8 million gallon rectangular settling pond. Total suspended solids at the outfall almost always hover right around 28 mg/liter. That's pretty clean considering that the water starts out as a slurry carrying 40% solids.

Lou

 

[LouH]

I have a bare bottomed display specifically to allow me to remove all of the detritus from the system weekly. Seems to me that more flow in the display woulk kerp detritus suspended, allowing more to go into the overflow where my 100 um sock would capture it. However, I have lots of shrooms and zoos which don't like hihg flow IME.

Lou

 

[Reefin' Dude]

the other problem is that a substrate will create its own detritus. so even if you could get "enough" flow to keep it from settling there, the give and take of calcium carbonate and bacteria will produce detritus within the substrate. no matter how careful one is, at some point a substrate is going to need to be cleaned of detritus.

here is the 30g conical tank i have to plumb into my new system when i finally get the go ahead from the "boss" on where i can put the display.

i originally bought this for my 125g system, so i may need to go with a 60g or larger with the 250+ new system. just turn a valve on the bottom and instant detritus removal. doesn't get much easier. though those that have them setup say some good whacks with a soft mallet help to get the detritus that sticks to the sides of the HDPE to drop to the bottom.

G~

 

[LouH]

the other problem is that a substrate will create its own detritus. so even if you could get "enough" flow to keep it from settling there, the give and take of calcium carbonate and bacteria will produce detritus within the substrate. no matter how careful one is, at some point a substrate is going to need to be cleaned of detritus.

here is the 30g conical tank i have to plumb into my new system when i finally get the go ahead from the "boss" on where i can put the display.

i originally bought this for my 125g system, so i may need to go with a 60g or larger with the 250+ new system. just turn a valve on the bottom and instant detritus removal. doesn't get much easier. though those that have them setup say some good whacks with a soft mallet help to get the detritus that sticks to the sides of the HDPE to drop to the bottom.

G~

I've seen chains pulled along the walls of conical clarifiers to dislodge material on the walls. The problem there would be suspended solids. I would probably go the route of having the ability to drain the whole thing through a filter and return the water back to the system after a clarifier rinse. Either that or have the ability to bypass the clarifier while the solids settle out. Purge the bottom and then put it back online. I don't know, detritus might not want to stick to the walls much, so it probably won't be that big of a deal. Just thinking out loud.

If you ended up needing to drain the whole thing through a filter, you would probably be better served by a filter in the first place. I like your approach though. Keep us updated.

Lou