BioGeoChemistry, Meiobenthology & Microbial Ecology of the Sandbed.

[bitts]

Thats what I was assuming,but you now what happens when you assume.

 

Of course its my fault since I wrote the write up, & then gave an overly short answer in my first response to the topic. Problem is that I really did just get to a point where it was becoming to long. Despite the fact that there still tons to cover. The version thats up was cut down from about 1100-1200 words to what it is now.

Edited February 19, 2011 by bitts

[bitts]

I am placing an order this week for more salt and the like and I want to try vodka dosing. Is there a benefit to using biopellets vs. MB7+vodka?

 

Do I need MB7 with the biopellets?

 

I've read quite a bit but I've read lots of conflicting information and the most up to date information is what I want to act on.

 

Is there a special brand that people have had the best experiences with? Is there multiple brands of MB7 or just this stuff:

http://www.marinedepot.com/Brightwell_Aqua...IADWTBS-vi.html

 

Also, I dose oyster feast and phyto feast. Keep up with that and increase other feedings?

 

Someone mentioned amino acids give the corals colors. This stuff?:

http://www.marinedepot.com/Brightwell_Aqua...IADTECS-vi.html

 

Thanks everyone!

 

**Yes I have a skimmer**

 

the fact you have a skimmer is good. keep in mind that with this it is very easy to over load the skimmers ability. turning it into a foam cannon. my euro-reef rs80 on 30gallons of total system volume never stops producing. I suspect that I need about 3 times the power than what I have because of the difference in design based ratings & on expected needs of a normal tank environment. compared to that of one which is a carbon-driven bacterioplanktonic system. many skimmers are built on old premises that go back to counter current skimmer design. like the inflow should come from the drain & be gravity fed through the skimmer this flow rate should be set so the tank volume flows through the skimmer 2x daily. which gets tricky since you mixing the filltered water back into the display. but the up side is that it allows for the tanks population of plankton & bacteria to have time to reproduce maintaining said population. while garaunting that all water that flows from the drain is filtered. the thing is that the normal tanks bacterial load is much lower than that of a system based on one which is a carbon driven bacterial based filtration. this is because the water column is saturated with bacteria much closer to the populations found in the actual reef invironment. which is that reason for doing this. after all the hole point of having a tank is to recreate the reef environment & if your goal is some thing else I would recommend other methods of going about this. but with this increase of organics in the water column the skimmer has a much greater percentage of the water column to pull from. meaning that the rating of the normal skimmer has nothing to do with your tank so as is always said get the biggest one you can. just try to match the drain rate to the skimmers intake as a minimum. while maximizing the air draw in relation to the through flow. also that if the skimmers inflow is higher than the drain rate than this will improve the skimmers ability to completely pull that which can be pulled. also that a skimmer is not a wonder drug for any system, for they only pull about a third of the organics present. based on how they function. the rest must still be dealt with by the system, on a biologic level. thus if the skimmer is being over driven reduce the drain flow. most tanks are well past the 2x daily drain rate.

 

so moving right along why on earth should this be done if there are other things that you can do. well its to increase the amount of nutrient in flux, after all the reef is not a nutrient desert. just the opposite only the life in that environment is so adapted at utilizing the available nutrients that none will register in the water column. this is often, & I would say mistakenly, refereed to as an ultra low nutrient system. mostly taken up to prevent the build up of trats. I would again say that this should be done to more acuratly create the reef environment with complete nutrient cycling the end goal. also enabling you to feed much closer to that of the natural state. which is close to 1oz of wet food for every 10gallons of water. (see what I mean about giving the skimmer something to actually do.) while maximizing the amount of nutrient in flux.

 

so what has this to do with carbon dosing vs biopellets. well its the method of inter action & its affect that matters. first the benefit of adding carbon is that it allows you to track this nutrient flux through the levels of p & n as a reflection of the the amount of carbon present. (since you can't test for carbon) controlled through the amount dosed. where in a normal system you are trying to control the amount of carbon present through the amount p & n added to the system, through feeding. from the view point of ecology, dosing carbon is just much more sound. far more complex & inherently more dangerous, but still more ecologically sound.

 

now how does this compare to the use of pellets. with the pellets present in the water column it is suppose to enable the bacteria to be self regulating where as in a standard dosing system you have to adjust the amount dosed to reflect the needs of the tank. but there is a part of me that says this is returning to having the carbon present in the water column & therefore may be possible of returning the system to one which is controlled by the the addition of n & p added to it. rather than the amount of carbon added but only time will give us data on this. based on this I would think that carbon dosing would still be needed with the use of pellets to maintain the same level of control. then one danger that is continually present based on this would be a sudden release of carbon from the pellets. which seems unlikely but would be comparable to poring a bottle of vodka into the tank.

 

as to sources of heterotrophic bacteria. MB7 is a great place to start & is what I use in my own system. others would be zeovit/Fauna-Marin Ultralith or Prodibio. but there are still others.

 

as to the current thoughts on pellets. I would pay no attention to them or at least veiw them with a sceptical eye. since there has been so little data gathered. but instead look at the pros & cons. then make an informed decision based on these & how you feel about them.

 

I'm sure that I didn't answer all of your questions but hopefully I didn't make things worse.

 

a couple of links I do like on the subject

http://pomakantha.wordpress.com/2011/02/13...-wonder-tonics/

http://pomakantha.wordpress.com/2011/02/18...s-and-the-reef/

 

then of course reefbuildes is full of info on this as well.

 

but this is also why biofiltration & water chemistry are really the same thing.

 

 

as always carbon dosing should be to help with the ecology, not as a stop gap on the build up of nitrates. Before starting it make sure to have at least some understanding on its full ecological effect.

[bitts]

Seem to Answer this ? A LOT , so standard issue answer is...

 

Cyano affects how the nutrients move through the trophic layers. Creating a localized state of eutrophication. This then prevents the normal cycling of nutrients to other areas. Be they, sand, rock, what not... This is what causes there to be such a serious outbreak when there is one. All the nutrients that would normally be handled by the bio filter are being consumed by the cyano. This is where the problem with cyano can come from.

 

The good bacteria may be killed off by this lack of nutrient flow. So reacting quickly & correctly is VERY important. It is also important to remember that cyano & other photo based bacteria will always be present in the system & that their presence is actually beneficial to the system overall. Thus knowing the things that are likely to set them off is the first step. Most notably this will be something like a sudden die off of plankton, resulting a momentary spike in the detritus level. But regardless of this root source. There will be a, even if incredible localized, a small change to have triggered the onset. Look to changes of water flow, sand distribution (damn snails), coral growth, anything that could have effected the nutrient flow into the pore water of the sand or their accumulation/stagnation on the rock. This will then help to eliminate the problem.

 

Keep in mind that this is normally where the subject of water flow normally enters into the situation. So make sure that there hasn't been something simple like a snail in a pump. But if possible increase flow. Try to have the water flow at around 5-10cm per second across the sand & enough to prevent detritus acumulation on the rocks.

 

Now with this knowledge lets move on to the next step. What is enabling the growth. Nutrient availability & light, combining with the localized eutrophication. To get past this all three must be dealt with. Light is the easy one, so run dark for a couple days. Be aware this will also cause a die off of plankton & the ensuing detritus. Nutrient availability & eutrophication are more problematic. But the result of running dark will be a a sudden release of the fixated nutrients. Yes this is eutrophication but it is on a much less localized scale & can therefore be dealt with by normal husbandry. aka Water changes.

 

Now this brings us to dealing with the nutrient availability. If left in the water when the lights come back on the ever present cyano will just bloom once again. So the timing of the water change is what matters here, as well as the amount. The water change must be done before the lights come back on & the size needs to be large enough to remove almost all available. Think 80%-90%.

 

After affects of the bloom can be seen in the afore mentioned Bacterial populations. This has to do with doubling rates & such. But the short answer is that if any died off from the change in nutrient flow they will need time to repopulate. To help with the nutrient levels during this the best bet is to use the bacterial population found in the water column to help process them. The easiest way to accomplish this is to. Add bacteria in the form of MB-7 or any of the other products available.

 

Just remember that the things that matter here are prevention of localized nutrient accumulation & water flow.

[bitts]

& this one keeps coming up.

 

Vacuuming sand & shallow sand bed depth.

 

1)Redox discontinuity layer

Area at which the O2 levels drop below that needed to sustain O2 based respiration. (ignoring things like sulfur & iron for now)

 

2) O2 stratifacation

Only the top 2mm are oxic. After that, the pore water begin's to have the O2 levels drop. This is called O2 stratification. This will continue through the sediment until the redox discontinuity layer. At which point, with the O2 having been been used up. You are left with the ever dreaded black sand (aka the hypoxic layer/also skipping a little bit of the complexity but Eeh.). In nature this is not a bad thing, but due to the system size of our tanks, Yes it needs to be avoided. Anyway. This change in O2 causes the sand to change color as it drops. So the likely hood of not having the sand change color is low & would actually show something to be wrong.

 

3) Benthic/Biogenic mixing depth & bioturbation.

The depth to which the things that live in the sand mix it. Thus affecting the O2 levels. The greater this depth, the more likely that sedimentation will be processed before simply accumulating in the void space.

 

Okay the point of a dsb is to have enough depth to meet that needed to have a complete mixing depth. This is what allows the deposited sedimentation to be fully processed, while being transported down through all oxic layers. If the sediment layer, our sandbed, does not provide for this mixing depth. Then at some point the nutrient levels can, will increase at a rate which exceeds the bacterias ability to use them. This results in a rapid drop in the O2 levels & the beds collapse releasing these nutrients back into the water column.

 

The point is that a ssb needs to be treated as if it is a bb system, preventing as much nutrient deposits as possible. In fact all tanks should be but thats another thread. Now, while if the bed its self is accumulating what ever in the void space. This will create the "time bomb" every one talks about & indicates that the bed needed to be shallower.

 

As to disturbing the bed, this will automatically change the O2 levels killing off most of the bacteria. Which is where the argument about whether to stir the sand or not actually comes from. The other part is that it can remove the fauna which is itself stirring the sand. This then results in the sudden loss of filtering ability & a greater biuld up of sludge in the sand choking off the bed even further.

 

so Ideally the bed needs to be shallow enough to Keep the O2 layer at around say 80%ish. While allowing for the pore water to be easily flushed. Simply by the pressure gradient from the systems flow, ideally. This will also lend its self to minimizing the effects of disturbance on the bacteria. Enabling snails to do most of the stirring for you, releasing most of the nutrients back into the water column before their accumulation becomes problematic. All of this of course depends on the grain size but figure about 2cm. if you are going to disturb the bed it should be in very small amounts at any single time. The bacteria have amazingly slow doubling rates taking up to months to populate a bed depending on the conditions.

 

Okay I should probably shut up by now. Sorry for the rant.

[jdl]

nice write up, my head hurts

[bitts]

nice write up, my head hurts

Sorry & Thank you.

[bitts]

It isn't the NO3 that fuels cyanobacteria as much as it is PO4. Many cyano species can fix their own nitrogen and don't need dissolved NO3.

 

Feed less and if you feed frozen foods make sure to thaw+strain+rinse them before you put them in the tank. You can also try some PO4 adsorbing GFO media as well.

 

This is a really good point that I don't think I've touched on. But as all ways trust in the Fosi.

[sae647]

Bare Bottom is mostly about water chemistry. Think of it like this - fish, despite everything you know, everything you've been told, are really just water. They look like they’re a solid. You've eaten them as if they where a solid, but no. It was a lie, they’re just water. Therefore, a bare bottom or Berlin type system, allowing for superb water quality, makes for extremely healthy fish and corals. The downside is that it only allows for a limited biologic filter to develop in the set-up.

 

the argument here is that fish are mostly water so that means water quality is important? what? is this supposed to be a humorous introduction?

[bitts]

the argument here is that fish are mostly water so that means water quality is important? what? is this supposed to be a humorous introduction?

Assuming this is a Question & not a statement. Yes husbandry will be easier to understand & improve. if a gestalt shift can be made, from the belief that fish are basically a solid to their being a liquid contained in a semipermeable membrane. The reasoning for the is the amount of chemical flux between the fish & surrounding water.

 

So if you got a laugh out of it great. Was that the original intention not really. Scientifically based perspective & the reason I believe Berlin systems are so effective. It is also why chemical stability is crucial. Why I believe it is better to do daily dosing of things like calc than the allow for these levels to drop & then be brought back up through water changes, which many believe to be sufficient for maintaining said stability. Why when doing a water change such critical care needs to be given to matching the chemical state of the system water. & why water change's are stressful to the system.

Edited April 30, 2011 by bitts

[Mini-Dude]

Nice Write man! I just finished it, I am some what confused but thats prolly the normall reaction from any 12y/o lol I'm going to email it to my science teacher if that ok, we hqave been talking about cycles and stuff in science, it pretty much ties together everything we have been learning and puts it into an aquarrium format

[bitts]

Go for it. doing so will be the fastest way to understand the parts which are a little over whelming. I'm of course happy to talk wit you about any of it as well, but its faster to talk with someone in person. Probably easier to understand too.

[Mini-Dude]

Go for it. doing so will be the fastest way to understand the parts which are a little over whelming. I'm of course happy to talk wit you about any of it as well, but its faster to talk with someone in person. Probably easier to understand too.

yeah, I just got to find his email addy first, I'm PMing you right now with a propsal

[Mini-Dude]

Hey bitts, can I share this on another forum if I link it to here?

[lucky38422]

This is an awesome thread for begginers! Thanks

[Subsea]

After 40 years of reefkeeping I am impressed with your knowledge of so many inter connected areas of science. You have pulled together an impressive technical paper. Consider this as material for a doctorate theosis.

 

While I agree with the science, some of your conclusions and some of your applications don't work for me. I have been skimmerless for 20 years with no water changes. I always use activated carbon. With cemical warfare in my mixed garden tanks, I can not test for these compounds econominally. Activated carbon is my proactive insurance to this complex topic. With use of dsb (6" deep of arroggonite 2mm-5mm) over a false bottom, I use bacteria for nutrient recycling and complex food webs. I stir the top inch of this sand bed and feed numerous filter feeders in the 75G display tank with Jaubert Plenumn. My refugium is the classic mud/vegatable filter. I use Calurpa Prolifera which I harvest regularly. Some goes to the fish as nutrient recycling, some goes to my compost bin for nutrient export. I also dehydrate this macro and eat as a salty veggie chip, which is good with beer. Remember, I like complex food webs with multiple nutrient pathways.

 

My current 75G main tank with 30G mud/macro refugium has been set up for ten years with no water changes. Yes, I vacumn sand as required with is very little. I never disturb the mud filter. It is putrid black and smells sulfide when disturbed. It is crawling with worms and feels spongy to the touch. I frequently stir the top inch of display sandbed and watch the filter feeders extend their tentacles into this marine snow storm. I feed all of my sandbeds heavily. I allow bioindicators to tell me if I am feeding enough.

 

This is a marvelous hobby. For me it is an addiction. I am well pleased to find a source of knowledge that has a balance of common sense. Great article, keep the dialogue coming. Don't lose the passion.

 

La bonne temps roulee,

Patrick

[SantaMonica]

Love info like the first post. Can read stuff like that for days. Not as detailed as research studies, so you don't get bogged down with testing methods, discussion, nucleotides, assays, etc.

 

As for testing for carbon, of coarse with high cost/complexity you can put a tracer on an input and measure the output, but that's a bit much for a hobby

[ChloroPhil]

Bitts, you're my hero. I'm a FW biogeochemist focusing on interactions and their influence on aquatic vegetation and have been curious about SW BGC. Excellent read!