Biopellets?

[ErikH]

http://www.alibaba.com/product/uk101058271-100890083-0/Pla_Pellet.html

sure looks like them!

[justahobby]

Says it's for lactic acid extraction and extruding?? The excerpt below doesn't mention the plastic being laced w/ carbon, but does say it's laced w/ a drug...


http://www.ncbi.nlm.nih.gov/pubmed/9876618


Poly(L-lactic acid), (L-PLA) pellets containing theophylline as a model drug were prepared with increasing bovine serum albumin...Same concept, but different use of the plastic pellet IMO

[Europhyllia]

did you ever read the link I posted to your rice thread? It had a summary of DIY pellets including their generic label. Might be easier/safer to just look for the same kind of plastic

[Europhyllia]

here you go:


Polyhydroxyalkanoate (PHA):

Information:
Speculated to be the main component of commercial NP Biopellets (Reference #1).

PRO:
- Many successful cases using PHA (NP Biopellets) in controlling NO3/PO4.

CON:
- Expensive, about $99 per 1000mL of commercial NP Biopellets.
- Very hard to find sources of PHA except commercial products, which is expensive.

Polycaprolactone (PCL):

Information:
Confirmed to be the main component of Instant Ocean's Nitrate Reducer.

Reefers here on RC using PCL:
http://www.reefcentral.com/forums/showthread.php?t=1830864
http://www.reefcentral.com/forums/showthread.php?t=1766100
http://www.reefcentral.com/forums/showthread.php?p=17382991

PRO:
- Completely bio-degradable by bacteria, and provide a carbon source similar to PHA. (Reference #1)
- Some commercial biopellets for reef aquarium are also using PCL. (Reference #1)
- Less expensive compared to PHA, many alternative products can be found, such as "Friendly Plastic Pellets".
- PCL pellets can be bought for about $22-30 per 1kg from various internet sites, even from China.

CON:
- Compared to PHA, there's still very limited information on how successful PCL can control NO3/PO4 in reef aquariums
(If any of you have successfully controlled NO3/PO4 using PLA as biopellet alternative, please share your story with us!)

Polylactic Acid (PLA):

Information:
Basically these are degradable plastic (polymers) derived from corn starch and sugercanes. (Reference #2)

In fact we've a reefer here on RC who'd DIY'ing these polymers from corn starch. (Reference #3)

Studies on waste water processing have shown that PLA with corn starch at 10% weight content receive the best nitrate reduction effects. (Reference #1)

PRO:
- Commercial PLA are relatively cheap.
- Can be DIY from corn starch with some effort.

CON:
- Slow decomposition rate (Reference #4), meaning it could take just too long for the starch to be released from the polymer form into the water.
- Not much information on how effective PLA can be use to control NO3/PO4 in reef aquariums.
(Again please share your story with us if you've successfully used PLA as alternative biopellets)

Granular starch (rice, wheat and corn):

Information:

Just the everyday grain that you consume in meals.

Referring to PLA above, the optimal % of weight content of starch to be used is about 10%, meaning if you were putting in 100g of commercial biopellets in your reef system, you should be using 10g of granular starch or else you could be overdosing carbon source.

Reefers here on RC using granular starch:
http://www.reefcentral.com/forums/showthread.php?t=1874551
http://www.reefcentral.com/forums/showthread.php?t=1878307

PRO:
- They're CHEAP and readily available in grocery stores.
- Studies showed that granular starches are proven means to provide carbon source for denitrification in waste water processing as well as recirculating aquaculture systems (RAS).

CON:
- Unknown effect on minerials released into water column.
- Relatively high phosphrous content that could shift towards a Nitrogen limited environment.
- Inconsistant rate of decompose means it could release too much carbon into the water.

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Sources and References:
1. Information on PCL, PHA and PLA (a very good read, recommended)
http://www.wamas.org/forums/topic/37366-diy-biopellets/page__st__25

2. PLA
http://en.wikipedia.org/wiki/Polylactic_acid

3. DIY corn starch polymer
http://www.reefcentral.com/forums/showthread.php?t=1780922

4. PLA decomposition rate
http://www.smithsonianmag.com/science-nature/plastic.html?c=y&page=1

5. Vinegar polymer encapsulation (have anyone even tried this?)
http://web1.reefcentral.com/forums/showthread.php?p=16572578