DIY biopellets

[OldReefer]

I've got a spare GSA media reactor I am not using if you need it. I'd just feed it with a MJ1200 located in the sump near your drain lines. I then put the output of the reactor as close as possible to the intake of the skimmer

[davelin315]

I have a few media reactors from Dan that I bought to assemble myself, as well as a phosphate reactor that I'm assuming I should take off line if I try this. If I tapped it off of the actual skimmer itself (mine is built to accommodate up to 4 pumps and I use 3) so that essentially it recirculated the water from the skimmer, would this work to my advantage? All of the water would be very oxygen rich (is it mainly aerobic bacteria that is sought in the biopellets or is there any sort of anaerobic activity anticipated as well?) and would be reintroduced to the skimmer to remove excess bacteria almost immediately. I don't know if the fine bubbles would be an issue mixed in with the biopellets, advice?

[Origami]

The little product literature that I've read speculates that there's an anaerobic layer under the aerobic layer of bacteria. I'm not sure that I completely buy that, though. If the water is too highly oxygenated - or if the pellets are aggressively tumbled - you may find that, while bacteria grow on the biopellets, nitrates in the water column may accumulate. This may be behind what Cliff was talking about earlier. This is pure speculation on my part, though.

[Matt LeBaron]

Looks like a number of people have been using these pellets for a couple of months now. Any longer term observations about whether they may become more standard in the hobby?

 

Coral Magazine has an article on them and similar techniques here. Was an interesting read but I still have some reservations, more or less Chad's second concern since I have seahorses also, but I run a skimmer so first concern is not an issue for me. I've had good luck with my seahorses by playing it safe with them but these pellets do intrigue me.

[davidm]

I'm finally getting around to thinking seriously about 'installing' these pellets bought in this group buy. Has anyone tried them yet? Any suggestions/comments/reviews? thanks, David

[zygote2k]

After 6 months of use, I can safely say that the biopellets haven't done anything but harm to my skimmerless system.

The N03 has been a steady 30ppm the whole time. I do weekly water changes and use carbon too. In the last 3 months, the tank has developed a serious cyano bloom. I even tried Mikrobacter 7 and the combination does nothing.

 

On the 3 other tanks that have skimmers, the pellets seem to reduce the No3 on one of them and none of them has developed a cyano issue. All of them were started with MB7 and all use carbon.

 

The jury is still out on this one and a better report will come after 1 year of use.

[Guest thefishman65]

I thought the recommendation was to have a skimmer. I thought all carbon dosing needed a skimmer to remove the bacteria. Otherwise it died and the cycle start over.

[Chad]

^the theory that I have heard is that without a skimmer, there is a much larger bacterioplankton population that can be used as food. If the system has a high demand on bacterioplankers for food (lots of stuff eats it), it can be done.

 

IMO, it is a superfine balance in a case like that and I think it would be very easy to miss the mark and end up with nutrient issues.

[Highland Reefer]

The little product literature that I've read speculates that there's an anaerobic layer under the aerobic layer of bacteria. I'm not sure that I completely buy that, though. If the water is too highly oxygenated - or if the pellets are aggressively tumbled - you may find that, while bacteria grow on the biopellets, nitrates in the water column may accumulate. This may be behind what Cliff was talking about earlier. This is pure speculation on my part, though.

 

Bacterial mats found on the bio-pellets as well as other surfaces found in a reef aquarium like rock and sand beds are quite complicated. They are composed of layers of different type of bacteria, both aerobic and anaerobic. The different types of bacteria act together as a whole to reduce the different waste products dissolved in reef tank water. Regarding the nitrogen cycle, the methods of brake down can take many forms as is depicted in this diagram: (Needless to say it is complicated.)

 

 

[Highland Reefer]

FWIW, BRS is now in the biopellet game. They are selling a PHA product at a good price. BRS's directions for use of their product are the best I have seen so far.

 

http://www.bulkreefsupply.com/store/BRS-Bio-Pellets

 

 

 

This is an interesting video demonstrating how quickly a bacterial biofilm can develop. Notice this video takes place over an 8 hr period. You can also see the biopolymer slime secreted by the bacteria developing around colonies, which adds to the protection of a bacterial colony as well as its complexity.

 

Some of the recent research has found that bacteria have some kind of a capability to intercommunicate with each other as well. At least they can detect other bacteria's presence to build these slime layers.

 

Wenyuan Shi Biofilm Formation

[Origami]

That's an interesting graphic, Cliff. It implies a bacterial mat approaching 3mm in thickness, though, before anaerobic bacteria come into play. (I'm assuming that those bacteria that are sulfide-metabolizing are doing so in the relative absence of oxygen.) Is this correct? Do mats of this thickness routinely develop on pellets?

 

BTW, I've swapped out the GFO on my system with PLA pellets (given to me by a manufacturer) but haven't arrived at any conclusion as to whether or not it's making a difference or if the PLA is being metabolized.

[Highland Reefer]

Another link that explains how the different type of bacteria found in bacterial biofilms utilize carbon and energy sources:

 

http://books.google....motroph&f=false

Edited November 28, 2010 by Highland Reefer

[Origami]

 

This is an interesting video demonstrating how quickly a bacterial biofilm can develop. Notice this video takes place over an 8 hr period. You can also see the biopolymer slime secreted by the bacteria developing around colonies, which adds to the protection of a bacterial colony as well as its complexity.

 

Some of the recent research has found that bacteria have some kind of a capability to intercommunicate with each other as well. At least they can detect other bacteria's presence to build these slime layers.

 

Wenyuan Shi Biofilm Formation

 

"In vitro simulation of biofilm forming on enamel surface as human saliva is pulsed over an initially clean surface."

 

That's our teeth after 8 hours!

[Highland Reefer]

Tom,

 

The first stage of forming a biomass is that single bacteria attach to the surface of the biopellets. You can actually see these biomasses on the pellets & if water flow through reactors or filter bags is to slow the polymers formed by bacteria that have congregated together will further glue the bacterial biomasses to the surface. As the biomasses continue to multiply, eventually the biomass become to large and water flow will slough off parts of the biomass. These biomasses left unchecked can get quite large. So the size of biomasses in the filters can be quite thick depending on water flow..........etc.

 

A large bacteria biomass:

 

Huge bacterial slime mass with diver

[Origami]

Thanks, Cliff. I understand the formation of the bacterial colony and even the bacterial mats.

 

What I'm wondering, though, is how much evidence is there that, under the operating conditions that we supply (tumbling within a flow of tank water) that the films that form on the pellets contain sufficient anaerobic bacteria that can complete the nitrogen cycle, metabolizing nitrates into nitrogen gas? On first glance, it seems that these pellets (which I have no reason to believe are porous) are in a highly oxygenated environment, and that the mechanical action of tumbling hinders the formation of a biofilm of any substantial thickness which might produce the oxygen-poor environment required of facultative aerobes to consume nitrates.

 

Is nitrate reduction happening on the pellet or elsewhere in the system?

[Highland Reefer]

BTW, I've swapped out the GFO on my system with PLA pellets (given to me by a manufacturer) but haven't arrived at any conclusion as to whether or not it's making a difference or if the PLA is being metabolized.

 

Well in a tank with low nutrient levels, low phosphate & low nitrate, even with an added carbon source available, bacterial growth rates may be slow. Still, I would assume you see good brown skimmate production, especially if feeding rates are higher. If your tank nutrient levels were previously low, I don't know that you would see any spectacular results. Some hobbyists experiment with added food sources which the biopellets would help prevent nutrient buildup and state they get better coral coloration. If your goal would be to increase fish populations I could see where the biopellets could help. Other than that, if your nutrient levels are low, I don't believe biopellets are necessary. I look at biopellets as a method for nitrate control & phosphate (if the added phosphate is not to high), where better filtration methods & the standard maintenance procedures are not adequate.

 

If you are able to stop using GFO where previously you could not, I would consider this an accomplishment. How the price comparison works out, I'm not sure.

[Origami]

Well in a tank with low nutrient levels, low phosphate & low nitrate, even with an added carbon source available, bacterial growth rates may be slow. Still, I would assume you see good brown skimmate production, especially if feeding rates are higher. If your tank nutrient levels were previously low, I don't know that you would see any spectacular results. Some hobbyists experiment with added food sources which the biopellets would help prevent nutrient buildup and state they get better coral coloration. If your goal would be to increase fish populations I could see where the biopellets could help. Other than that, if your nutrient levels are low, I don't believe biopellets are necessary. I look at biopellets as a method for nitrate control & phosphate (if the added phosphate is not to high), where better filtration methods & the standard maintenance procedures are not adequate.

 

If you are able to stop using GFO where previously you could not, I would consider this an accomplishment. How the price comparison works out, I'm not sure.

 

I actually pulled the GFO because I felt that my tank was possibly running too clean (my operating hypothesis) and that the lack of phosphates might have negative consequences at the bottom end of the food chain. The only evidence I had of this was a virtual stop in the growth of my macroalage, a collapse in my pod population, and pockets of a rather stubborn cyanobacteria showing up. I pulled the GFO (to add a phosphate food source), added the PLA (to provide an ongoing carbon source and additional surface area for colonization), and re-seeded the tank using Microbacter-7 (and even a septic bacteria source) to encourage diversity.

 

Since the tank is nutrient-poor, it will take time to notice any difference. The only difference I'm expecting that I'll be able to see may come from a depletion of the pellets (reduction in pellet volume). That may take some time. So far, phosphate readings from my hanna checker are still zero, and I'm not seeing an explosion of green algae on my glass. So, if there are phosphates to be had, I'm assuming that bacteria are having it. It's still too early to tell, though.

[Highland Reefer]

Thanks, Cliff. I understand the formation of the bacterial colony and even the bacterial mats.

 

What I'm wondering, though, is how much evidence is there that, under the operating conditions that we supply (tumbling within a flow of tank water) that the films that form on the pellets contain sufficient anaerobic bacteria that can complete the nitrogen cycle, metabolizing nitrates into nitrogen gas?

 

IMO, if you can see the biomasses, they are thick enough to reduce the N sources including nitrate to N2. There are different pathways that nitrate can take to get to N2 gas. The gelatinous secretions produced by bacteria, do reduce O2 from entering and circulating around as the biomass grows and at the same time allow the smaller molecules to enter and circulate. Nutrients are absorbed by the aerobic organisms and then their byproducts are passed down from bacterial type to bacterial type into the anaerobic portions of the biomass.

 

 

Is nitrate reduction happening on the pellet or elsewhere in the system?

 

IMHO, these biopellets are not the best substrate to grow biomasses on, based on the research for the Instant Ocean PCL patent and results I have seen hobbyists accomplish on one thread on RC. From the IO patent it is obvious that the bacterial biomasses grow and multiply quicker when 4-6 cm diameter gravel is mixed in with the biopellets. The hobbyists that have tried this are able to replace anywhere from 30% to 70% of the biopellets with the coarse gravel with the same results. Obviously the gravel provides a better substrate for bacterial biomasses to grow.

 

As far as whether the pellets get into the water column, I would assume that there is at least some sloughing off of the pellets and perhaps some material is dissolved into the water column, I don't know and have seen no research regarding this.

[Origami]

IMO, if you can see the biomasses, they are thick enough to reduce the N sources including nitrate to N2.

 

I've not yet seen much in the way of a biofilm that is visible to the naked eye. I'm only assuming that it's there at this point. The pellets have been in the system for around 2 months now.

 

From the IO patent it is obvious that the bacterial biomasses grow and multiply quicker when 4-6 cm diameter gravel is mixed in with the biopellets. The hobbyists that have tried this are able to replace anywhere from 30% to 70% of the biopellets with the coarse gravel with the same results. Obviously the gravel provides a better substrate for bacterial biomasses to grow.

 

Now that's interesting! Gravel would, depending upon the material used, have pits and perhaps even some advanced level of porosity which might provide increased anaerobic volume. So you can use half the pellets and obtain the same results? Was there any discussion on specifically what the gravel was made of? Was this an aragonite gravel? Quartz or some other silicate? Or did it matter?

[Highland Reefer]

I actually pulled the GFO because I felt that my tank was possibly running too clean (my operating hypothesis) and that the lack of phosphates might have negative consequences at the bottom end of the food chain. The only evidence I had of this was a virtual stop in the growth of my macroalage, a collapse in my pod population, and pockets of a rather stubborn cyanobacteria showing up. I pulled the GFO (to add a phosphate food source), added the PLA (to provide an ongoing carbon source and additional surface area for colonization), and re-seeded the tank using Microbacter-7 (and even a septic bacteria source) to encourage diversity.

 

Since the tank is nutrient-poor, it will take time to notice any difference. The only difference I'm expecting that I'll be able to see may come from a depletion of the pellets (reduction in pellet volume). That may take some time. So far, phosphate readings from my hanna checker are still zero, and I'm not seeing an explosion of green algae on my glass. So, if there are phosphates to be had, I'm assuming that bacteria are having it. It's still too early to tell, though.

 

 

Removing the GFO sounds good as well to me as long as your pests stay under control and your phosphate levels don't climb to detectable levels.

 

Trying to control cyano and pest algae while maintaining needed nutrients for your coral is trickly as you know. Only close observations will tell. Hopefully removing the GFO will allow needed nutrients to allow your coral to grow better. I noticed in my system, that running too much GFO did slow the growth of my coral, and I stopped using it with better results. Perhaps running too much carbon could strip too many nutrients from your system as well. Experimenting with how often you run GAC may show benefits as well.

[Origami]

Removing the GFO sounds good as well to me as long as your pests stay under control and your phosphate levels don't climb to detectable levels.

 

Just took another phosphate measurement. It was 0.00 ppm again (according to the Hanna checker).

 

I noticed in my system, that running too much GFO did slow the growth of my coral, and I stopped using it with better results. Perhaps running too much carbon could strip too many nutrients from your system as well. Experimenting with how often you run GAC may show benefits as well.

 

That's what I was seeing as well. Since pulling the GFO, growth seems to have picked up again. I've cut back on the carbon, too.

[Highland Reefer]

I've not yet seen much in the way of a biofilm that is visible to the naked eye. I'm only assuming that it's there at this point. The pellets have been in the system for around 2 months now.

 

 

 

Now that's interesting! Gravel would, depending upon the material used, have pits and perhaps even some advanced level of porosity which might provide increased anaerobic volume. So you can use half the pellets and obtain the same results? Was there any discussion on specifically what the gravel was made of? Was this an aragonite gravel? Quartz or some other silicate? Or did it matter?

 

 

The gravel used was aragonite in both the patent and by several hobbyists that are successfully doing this now. Fine sand does not work per the patent, only the coarse gravel. The aragonite gravel would be much more porous than quartz.

[Origami]

The gravel used was aragonite in both the patent and by several hobbyists that are successfully doing this now. Fine sand does not work per the patent, only the coarse gravel. The aragonite gravel would be much more porous than quartz.

 

Most interesting. I figured it would be aragonite, but had to confirm. Gravel makes sense. I assume it's no longer tumbling but is an evenly dispersed mixture. Is this correct? Were any other configurations tested? For example, pellets followed by gravel or live rock rubble (downstream)?

[Highland Reefer]

Tom,

 

Perhaps your system is too low in nutrients, since you don't see growth on the biopellets. Poor coral growth with low nutrient levels would imply this to me. It can't be off by much though.

 

 

[Origami]

Tom,

 

Perhaps your system is too low in nutrients, since you don't see growth on the biopellets. Poor coral growth with low nutrient levels would imply this to me. It can't be off by much though.

 

Remember, though, it's PLA not PHA (or PHB). I was unable to have anybody sample me a few pounds of PHA, but I was able to get a couple of kilos of the PLA without too much difficulty. Since I had it lying around, I decided to give it a go.

 

My not seeing the biofilm is probably a combination of things, not the least of which are middle aged eyes!