The short version
- Typical range: £25 – £180 — see the full aquarium value guide
- What decides your price: condition, and how well you evidence it in photographs
- Cost to sell here: nothing, at any price
- Category: Pet Supplies
Before you photograph it
Ten minutes here is worth more than anything else you will do. Buyers are deciding between your listing and someone else’s, and preparation is what visibly separates the two.
- List every piece of equipment: filter and model, heater wattage, lighting unit, air pump, substrate, decor and cabinet.
- Test the filter and heater are working before you list, and note the age of each.
- Fill the tank and leave it standing for a few hours to check the seals, then drain it. A seal leak found by the buyer at home is a very bad outcome.
The photographs that sell an aquarium
Four photographs do almost all the work. Shoot in daylight, near a window, with the item against something plain — and do not use the flash, which flattens texture and hides exactly what buyers are trying to see.
- The aquarium set up and running, whole, including the cabinet
- All equipment laid out together — filter, heater, lights, pump
- The silicone seals along the inside corners, close up
- The glass edges and base, plus any scratch, chip or limescale line
Photograph the flaws too. It feels counterproductive, but a listing that shows the worst of an item gets fewer questions, fewer withdrawn offers and fewer arguments at handover. Buyers who can see the damage stop imagining something worse.
Writing the title and description
Volume and completeness: “180L Aquarium with Cabinet, Filter, Heater and Lights”. Litres is the search term. Naming the filter model matters because external filters are expensive and buyers recognise the good ones. Say tropical, marine or coldwater if the setup is specific to one.
Then state these in the description, because a buyer who has to ask is a buyer who might not bother:
- Volume in litres and external dimensions including the cabinet
- Every piece of equipment included, named with model where known
- Age of the tank and the silicone, and whether the seals have been tested
- Whether the cabinet is included and its condition
What buyers will actually ask
You will receive the same three messages about an aquarium. Answering them in the listing itself removes the back-and-forth, and answering them well when they do arrive is what turns an enquiry into a sale.
Fill it, leave it standing and report the result. Silicone perishes with age and this is the question every experienced fishkeeper asks first.
Name the model. A good external filter can be worth a large share of the whole setup and buyers search for them specifically.
Give your honest best estimate. Tanks over about ten years old are often resealed by the buyer as a matter of course, and saying so is better than being asked.
Pricing it so it actually sells
Start from the honest condition grade rather than the price you hope for. WishThrift listings use five grades — New with Tags, Like New, Good, Fair and For Parts — and what each grade means is worth reading before you choose, because grading up is the most expensive mistake sellers make. It does not raise the price; it produces a buyer who arrives expecting something else.
The aquarium value guide prices all five grades for this item. Pick your grade, take the figure, and if you sit between two grades price toward the lower one. Items priced honestly sell faster than items priced hopefully, and on a free platform there is no fee eating the difference anyway.
What you keep, compared
On a £102 sale — roughly the middle of the range for an aquarium — here is what the commission-charging platforms would take, and what you would keep on each:
| Where you sell it | Fee | You keep |
|---|---|---|
| WishThrift | £0 | £102 |
| Poshmark | −£20 | £82 |
| eBay | −£14 | £88 |
| Mercari | −£10 | £92 |
| Etsy | −£7 | £95 |
Seller-side rates verified 26 Jul 2026 — Poshmark: 20% commission on sales of $15 and above; eBay: 13.6% final value fee, plus a per-order fee; Mercari: flat 10% selling fee; Etsy: 6.5% transaction fee, plus a listing fee and payment processing. Percentages are applied to the sterling figure above; the fixed per-order and processing charges those platforms add are quoted in their own currency and are not included here, so the real deductions are slightly larger. Full breakdown: marketplace selling fees compared.
Timing and getting it to the buyer
Steady year round, with a lift in autumn and January when people start indoor hobbies. Large complete setups with a cabinet sell within a fortnight; bare tanks are slower — see the fish tank guide if that is what you have.
Collection only, fully drained and with the substrate removed. A filled tank must never be moved even a short distance — the flexing cracks the seals. Transport it flat and supported, never on an edge.
WishThrift does not process payments or arrange delivery — you and the buyer agree both directly — so confirm payment has cleared before the item leaves your hands, and keep the conversation on the site so there is a record of what was agreed.
Ready to list it? It takes about two minutes, costs nothing, and there is no commission when it sells — create a free account or see how selling works.
Frequently asked questions
What is a used aquarium worth?
Typically £25 to £180 for a complete setup, driven mostly by volume and the equipment included. See the aquarium value guide for the condition bands.
Should I sell the fish with it?
Livestock is a separate matter and needs to go to someone equipped to receive it, ideally rehomed through a local aquatics shop or fishkeeping group rather than bundled into a marketplace listing.
Can I move a tank with water in it?
No. Even a few centimetres of water flexes the base enough to break the seals, and a large tank is heavy enough to be dangerous. Drain it completely first, every time.
See also: what a used aquarium is worth · browse live pet supplies listings · condition grades explained.