Invertebrate
Clam (Tridacna / Derasa) — What's a Fair Price?
Based on 22 in-stock listings across 1 online reef vendor, updated October 20, 2026.
A typical Clam (Tridacna / Derasa) sells for around $179.99 right now. Anything near $129.99 is at the cheap end of today's market. Prices below are the cheapest current listing per vendor.
Cheapest per vendor
| Vendor | Listing | Price | |
|---|---|---|---|
| Top Shelf Aquatics | Ultra Squamosa Clam 1-2" | $129.99 | view → |
Shipping differs by vendor (free-shipping thresholds, flat overnight rates) and can change which vendor is cheapest to your door.
Reading today's numbers
Today's 22 in-stock listings span $129.99 to $449.99 — the high end is 3.5× the low. For invertebrates, a gap like that usually reflects listings at different sizes or grades rather than one vendor simply overcharging. The $179.99 median is the fairest single benchmark: half of those listings sit at or below it.
Only one of the vendors we track currently lists it, so this range reflects a single store's listings rather than a cross-vendor comparison — worth keeping in mind when judging the price.
Keeping it alive once it arrives
Disclosure: the Chewy links below are affiliate links — if you buy through them we earn a commission, at no extra cost to you. This never affects the prices or vendor rankings above. Details.
Invertebrates tolerate swings in salinity and water chemistry worse than most fish do, so consistent mixing and regular testing matter more here than anywhere else in the tank. Chewy — a general pet retailer that sells no live coral or marine fish, and is not one of the vendors this index tracks — carries reef salt mixes, saltwater test kits, marine fish food, and coral and invertebrate food.
Price history
The market median for Clam (Tridacna / Derasa) has changed 17 times in 100 days of tracking. Median shifts here usually come from vendor promotion events or the in-stock mix changing rather than gradual drift (how these prices actually behave) — genuine repricings land on the price drops page as we observe them.
Common questions
Every answer below is computed from this page's own numbers at build time, and updates with the daily data refresh.
- How much does Clam (Tridacna / Derasa) cost?
- The median price is $179.99, based on 22 in-stock listings across 1 online reef vendor as of October 20, 2026. The range runs from $129.99 at the low end to $449.99 at the high end. Only one of the vendors the index tracks currently lists it, so this reflects a single store's listings rather than a cross-vendor comparison.
- Which vendors sell Clam (Tridacna / Derasa)?
- 1 of the online reef vendors the index tracks lists it as of October 20, 2026: Top Shelf Aquatics at $129.99. Each figure is that vendor's cheapest current listing.
- Has the price of Clam (Tridacna / Derasa) changed?
- Yes. The market median has changed 17 times across the 100 days the index has tracked it. Shifts here usually come from vendor promotion events or the in-stock mix changing rather than gradual drift.
- Is Clam (Tridacna / Derasa) in stock right now?
- 22 of the 26 listings the index tracks for it were in stock as of October 20, 2026, across 1 vendor.
Cite this page: Reef Price Index, "Clam (Tridacna / Derasa) price," data through October 20, 2026. https://reefpriceindex.com/species/clam
Related reading from our data
We check Clam (Tridacna / Derasa) prices at every vendor we track, every day. How the index works.