Recyclable Corrugated Polypropylene Boxes For Shipping Fresh and Frozen Seafood
Recyclable corrugated polypropylene boxes for shipping fresh and frozen seafood
If you're shipping seafood, your packaging has to deal with things most boxes aren't built for: ice melt, refrigerated trailers, wet processing floors, and a lot of handling between the dock and the customer. Waxed corrugated softens and foam cracks and sheds beads, making both products a hassle to dispose of.
CoolSeal makes seafood boxes out of corrugated polypropylene (PP5) instead. The material doesn't absorb water and won't break down when it's wet, so the box keeps its shape, and your product stays clean and protected through the whole cold chain. The boxes ship flat, recycle as PP5, and can be printed with your branding.
Below is a quick guide to which box fits what you're shipping, how it compares to foam and waxed corrugated, and how to get a quote.
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Industry Leading & 100% Recyclable Fish Boxes
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20# Shellfish Box
Which Box Do You Need?
We make seafood boxes in standard sizes for most fish and shellfish operations, plus custom dimensions when you need them. All of them arrive flat and pre-folded, and assemble in one motion at the packing line.
Fish and fillet boxes come in 5, 10, 20, and 30 lb. capacities, a 13 kg box, 10 and 20 lb. fillet boxes, and a dedicated salmon box. These are the everyday workhorses for whole fish, fillets, and portioned product.
Shellfish boxes are built for oysters, clams, mussels, crab, and lobster, where you're dealing with shell, liquid, and ice. You have a few options depending on how you handle meltwater:
The #10 and #20 Shellfish Boxes are leakproof one-piece boxes with fold-over lids and locking tabs that keep everything sealed inside — the right choice when you want nothing leaking out, including for air freight.
The 20# Shellfish Box gives you a larger leakproof option for higher-volume runs.
If none of the standard sizes line up with your portion weights or pallet layout, we can extrude a custom box. Talk to us about your dimensions, and we'll size it to fit.
How It Compares To Foam And Waxed Corrugated
A few practical differences tend to matter most to seafood shippers:
It saves space and freight.
Because the boxes ship flat, they take up roughly 85% less storage than pre-assembled foam. And since the outer dimensions are smaller than foam while holding the same amount of product, you can fit more per pallet and cut your freight cost per shipment.
It holds up when wet.
Polypropylene doesn't wick moisture the way fiber board does. Our sealed edge — where we heat-seal the open flutes of the board shut — keeps water out of the structure and keeps the box rigid even after sitting on ice.
It's cleaner to run.
Sealing those flutes also means there's nowhere for bacteria to collect, and the boxes are certified for direct food contact. No foam beads breaking off into your facility, and less mess to clean up around drains.
It can actually cool faster.
This one surprises people: foam's thick insulation can slow how quickly product reaches chill temperature in a refrigerated chain. Because our boxes carry less bulk insulation, product tends to pull down to temperature faster, which helps quality and shelf life.
It's genuinely recyclable.
Every part of the box is PP5 and recyclable, which keeps disposal costs down and holds up against the recyclability claims a lot of waxed packaging makes but can't really deliver.
| Feature | CoolSeal Polypropylene | Waxed Corrugated | EPS Foam |
|---|---|---|---|
| Holds up when wet | Limited | ||
| Recyclable (PP5) | Often difficult | Limited | |
| Ships flat | No | ||
| Flexes without breaking | Moderate | Sheds beads | |
| Food-safe sealed edge | No | No | |
| Custom printing | Limited |
Seafood box specifications
Standard sizes. Custom sizing available — 10,000 unit minimum, 2–4 week lead time.
| Box / size | Inside dimensions (L × W × H, in.) | Weight capacity | Machine erectable |
|---|---|---|---|
| 5 lb. box | 14.00 × 9.25 × 2.75 | 5 lb. | Yes |
| 10 lb. box | 14.00 × 9.25 × 4.25 | 10 lb. | Yes |
| 20 lb. box | 14.00 × 9.25 × 6.50 | 20 lb. | Yes |
| 13 kg box | 22.00 × 11.25 × 5.50 | 25 lb. | Yes |
| 30 lb. box | 22.00 × 11.25 × 6.75 | 30 lb. | Yes |
| 10 lb. fillet box | 22.50 × 7.50 × 3.88 | 10 lb. | Yes |
| 20 lb. fillet box | 22.50 × 7.50 × 5.13 | 20 lb. | Yes |
| Salmon box | 29.88 × 9.00 × 7.00 | 40 lb. | Yes |
All boxes ship flat and are erectable on automated packing lines.
Need a size that isn’t listed? Custom boxes are available with a 10,000 unit minimum and a 2–4 week lead time.
Product Information & Research
Shipping By Product
Not sure which page fits your catch? Here's where to look:
Fish Boxes — whole fish, fillets, and salmon, in the standard and fillet sizes above.
Oyster Boxes — leakproof and draining shellfish boxes that keep oysters cold and presentation-ready.
Lobster Boxes — watertight boxes built for the moisture and handling that come with shipping lobster.
Custom Printing And Branding
If you want your boxes to do double duty as packaging and marketing, we print them in-house with high-speed flexographic UV, multi-color screen, and digital printing. That's how seafood processors, distributors, and wholesalers put their logo and product info on the box so it travels with the product to the retail case.
A Bit About Us
CoolSeal technology was developed for the seafood industry in Grimsby, UK, and has been used across Europe for more than 30 years. We manufacture for the North American market in a zero-waste facility in Perrysburg, Ohio, and we're one of only a handful of plastic corrugated extruders in North America, which means we make the material and build the box, rather than buying one and selling the other.
We work with seafood processors, distributors, wholesalers, commercial fisheries, exporters, markets, grocery and foodservice suppliers, and cold storage operations.
Get A Quote
Tell us what you're shipping, your typical portion weights and volumes, and whether you need standard or custom sizing, and we'll recommend the right box and get you pricing. If you're currently on foam or waxed corrugated, we can usually fit into your existing line with little disruption.
Contact us to talk through your seafood packaging.
Frequently Asked Questions
What sizes do CoolSeal seafood boxes come in?
Stock seafood boxes range from 5 lb to 50 lb. Fish boxes come in 5, 10, 20, 30, and 50 lb, plus a 13 kg size. There are also 10 and 20 lb fillet boxes and a salmon box. Shellfish boxes include #10 and #20 leakproof boxes, a #10 draining box, and a 20# shellfish box. Stock fish boxes are white and unprinted. Inside and outside dimensions are on the Seafood Box Standard Sizes flyer.
What is the minimum order for CoolSeal boxes?
Minimums depend on the product. Stock seafood boxes start at 1 pallet. CSA crop boxes start at 1 bundle of 25 boxes. Custom orders start at 10,000 units for seafood boxes and 1,400 units for agricultural boxes.
How long does it take to get CoolSeal boxes?
Stocked boxes ship in 2 to 7 days. Custom designed or printed boxes take 3 to 5 weeks, depending on the project. Transit time depends on the carrier and your destination.
Does CoolSeal offer free samples?
Yes. CoolSeal sends free samples of stocked boxes, up to 5 per request, and pays the shipping. Samples let you test fit, strength, and packing on your own line before you order.
What is the difference between leakproof and draining seafood boxes?
A leakproof box seals everything inside, including meltwater, which is the right choice for air freight. A draining box has permanent drain slots that let meltwater run off during transport while the product stays in place. Some operations use both, depending on the shipment.
Do I need a liner in CoolSeal boxes?
No. You can safely pack fresh protein in CoolSeal boxes without a clear plastic liner. By contrast, Alaska Air Cargo requires waxed corrugated (wet-lock) boxes to be sealed in a 4-mil polyethylene liner, which adds cost and labor.
Fish shipping boxes | Alaska Air Cargo seafood rules
Can I ship seafood by air in CoolSeal boxes?
Airlines set their own packaging rules, so confirm with your carrier before you ship. CoolSeal's leakproof one-piece boxes hold all meltwater inside, which is what carriers look for. Most carriers do not accept wet ice and prefer gel packs or marked dry ice. Alaska Air Cargo, for example, generally limits seafood shipments to 100 lb.
Fresh seafood boxes | Alaska Air Cargo seafood rules
How do CoolSeal boxes compare with waxed corrugated and Styrofoam?
CoolSeal boxes are reusable, keep their strength when wet, and ship flat. Waxed corrugated softens when wet, and Styrofoam can crack and shed beads. Traditional wax-coated boxes are also generally not accepted in standard cardboard recycling, and Alaska Airlines does not accept Styrofoam for seafood checked as baggage.
| Feature | CoolSeal (PP5) | Traditional Waxed Corrugated | Styrofoam (EPS) |
|---|---|---|---|
| Strength when wet | Holds its shape | Softens | Can crack |
| Ships flat | Yes | Yes | No |
| Liner needed | No | Yes for air freight: 4-mil polyethylene (Alaska Air Cargo) | Varies by carrier |
| Recycling | PP5 recyclable | Generally not accepted | Limited |