Second-hand aquarium equipment: what to accept, what to refuse?
Buying used, the rule is simple: accept what is inert, be wary of what heats up or ages. A recent tank, a cabinet, stones, a gravel cleaner: yes, at half price. A heater over 2 years old, antique T8 lighting, opened test kits: no, whatever the discount. This buying grid can cut your setup bill by 40 to 60 %.
Which second-hand equipment is a good deal?
- The tank: glass doesn’t wear out; check the seals and edges, as detailed in new or second-hand aquarium.
- The dedicated cabinet: 50 to 70 % off; inspect for moisture marks on the back and under the feet.
- Brand-name external filters: nearly indestructible; ask to see them running, budget 10 to 15 € for new gaskets.
- Stones and resin decor: a white-vinegar clean and they’re good to go.
- Inert accessories: nets, scrapers, buckets, plant tweezers — virtually indestructible.
What should you refuse even at a knock-down price?
The second-hand heater first: it’s the most dangerous failure (thermal runaway or a mid-winter shutdown), for a new price of 15 to 25 € — the saving is never worth the risk. Also refuse T8/T5 fluorescent lighting (tubes to replace, twice the consumption of an LED), used filter media from an unknown tank (health risk), opened products and test kits (unverifiable expiry) and any tank with lifting seals.
How do you test the equipment in front of the seller?
Insist on a working demonstration: the filter plugged in over a bucket of water (strong flow, no bearing noise), the lighting on for ten minutes (no flickering), the air pump running. For the tank, run a fingernail along the inner seals and photograph the corners. A seller who refuses a demonstration is probably selling a breakdown. Reference prices for new gear, useful for negotiating, are in our fishkeeping accessories category.
What prices should you aim for second-hand?
Benchmarks seen on classified sites: bare 100-litre tank, 30 to 50 €; complete 120-litre kit with cabinet, 100 to 180 €; brand-name external filter, 40 to 60 % of new; decor and stones, 30 to 50 % of new. Combined with targeted new purchases (heater, tests, conditioner), a complete start-up drops below 250 € where all-new costs 450, as shown in our 120-litre budget.
Frequently asked questions
A complete aquarium sold with the fish in it — good idea?
Tricky: you have to move the livestock the same day, with no health-check period. Accept only if the tank is visibly healthy and the journey short.
How do you disinfect second-hand equipment?
Diluted white vinegar, a thorough rinse, 48 hours of complete drying: most aquatic pathogens don’t survive dryness. Never bleach on the seals.
Are second-hand air pumps reliable?
Yes, if they run quietly when tested; the diaphragm, the only wearing part, is replaced for 3 to 5 €.
This guide is part of Planète Pets’s Fishkeeping universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.