Anaerobic seed marketplace
Healthy seed for your digester.Tested, hauled, delivered.
Seed Sludge connects treatment plants that have surplus digestate with plants that are starting up or recovering a digester. We run the lab panel, book the lined tanker or reefer, and hold the deal in escrow, so you get a viable seed without the phone calls.
Need seed and can't find it? Post a need and let sellers come to you.
Egg-shaped · Mesophilic · Live draw
High-activity mesophilic seed
Large regional plant · Sacramento Valley, CA
- Volatile solids
- 63% of TS
- pH
- 7.3
- Alkalinity
- 3,600 mg/L
- VFA : Alk
- 0.15
- Fecal coliform
- 9.5×10⁴ MPN/g (Class B)
- Methanogenic activity
- 0.18 g COD/g VS·d
Available
150,000 gal
Seed price
Free
- gallons listed
- ~1M
- gallons listed
- states with supply
- 10
- states with supply
- typical lab turnaround
- 48 hr
- typical lab turnaround
- for most seed. You pay logistics
- $0
- for most seed. You pay logistics
How it works
One platform from draw-off to delivery
Digester startups usually seed 10–30% of working volume. That's tens of thousands of gallons of live biology that has to arrive on time and stay viable. We built the marketplace around that logistics problem.
For buyers
Starting up or recovering a digester
- 01
Browse or post a need
Filter by digester type, temperature regime, VS, pH, VFA:Alk, pathogen class, age and distance.
- 02
Get a delivered quote
One price covering seed, hauling, lab panel and fees, worked out from real distance and volume.
- 03
Lock the deal
A 20% deposit goes into escrow. The seller's contact unlocks so you can coordinate the site visit.
- 04
Receive verified seed
Pre-ship lab results land before the truck rolls. You sign off on delivery.
For sellers
Plants and digester operators with surplus
- 01
List in 3 minutes
Digester type, volume, recent lab values, loading access. Your plant stays anonymous.
- 02
Answer relayed questions
Buyers ask through the platform. Contact details are removed automatically until a deal locks.
- 03
We dispatch the hauler
Lined tankers, totes or reefers arrive on schedule. No trucking to arrange.
- 04
Get paid, offload solids
Payment on delivery sign-off. Often cheaper than land application or disposal.
The logistics layer
Shipping live biology is the hard part
Every quote picks the right equipment for your volume and distance. Our carriers are vetted for biosolids hauling, and every load runs under chain-of-custody paperwork.
Lined tanker
6,000 gal / load
Dedicated poly-lined vacuum tankers, washed and certified between loads so nothing cross-contaminates.
IBC tote hauling
275 gal / tote
New food-grade totes with vented caps for small volumes, granular sludge, or sites with no tanker access.
Refrigerated runs
4–10 °C · 250+ mi
Reefer trailers slow metabolism and gas build-up so long-haul seed arrives viable. Temperatures are logged for the whole trip.
Third-party lab panel
~48 hr turnaround
Independent lab sampling before shipment: solids, pH, alkalinity, VFA, pathogens, and optional methanogenic activity.
Available now
Fresh, lab-verified supply
Transaction protection
We own the transaction, so nobody gets cut out.
Contact details stay hidden until a deal locks. Once it does, both sides are covered by escrow, insurance and the same non-circumvention terms. Buyers can't be undercut and sellers can't be stiffed.
How protection worksHidden contacts
Plant names, people and addresses are masked until a deal locks.
Escrowed payment
The deposit is held by us and released when the buyer signs off on delivery.
Chain of custody
Lab results, bills of lading and temperature logs in one record.
Need seed by a date?
Post your volume, digester type and deadline. Matching sellers respond through the platform.
Paying to dispose of digestate?
List your surplus. Another plant's startup can be cheaper for you than hauling it to land application.