How to buy second hand tanks


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Not all of us can afford a shiny new aquarium. Nathan Hill has some advice on buying second hand set-ups.


Christmas, that excuse for drunken gluttony, film marathons, lavish gifts and an absolute rejection of moderation, is fast approaching. Hopefully you've all made up your wish lists and left them in convenient places for spouses/parents/benevolent millionaires to find. After all, it's been a good year for new fishkeeping gear, assuming you like LEDs, of course.

Understandably, not everyone can fork out for a brand new, shiny-boxed, esoteric dials and diodes aquarium. I know I can't this year, but thankfully for me I've got other folks' gear on trial, so I don't have to. But without that, I'd be having a right sulk this month.

Ergo, it's round about this time of year that a lot of buyers might be turning to second hand set ups to fill the watery voids in their fishkeeping hearts. That's how I got so heavily involved in the hobby, all those years ago. Perusing the free ads, picking up tattered and scuffed old gear, until my house was bulging with wonky-legged stands, and fizzing, rusty hoods.

We increasingly 'buy clever' these days, and we're all aware that the value of many new goods plummets the moment you take them out of the box. Why pay a premium for something spanking new? Well, there are a few reasons, but we'll get to those.

It was only a few months back that I wrote about the perils to livestock when using the classified ads to feed your hobby so I'm only going to give it a cursory mention here. You buy anything with fish at your own risk.

If you snaffle a bargain tank that turns out to have a Red tailed catfish in it, don't be in the least bit surprised when your local store tells you for the first time ever (and possibly with only limited tact) that you're on your own with it, and they will not be rehousing it for you.

However, the biggest screw up in buying second hand tanks complete with fish comes courtesy of ill-handled filters. Very few people know how to move a filter from one place to another without killing it off. So let's get that out of the way now...

Transporting safely!

First of all, politely ask the seller of the tank NOT to give everything a complete freshen up before you come to collect. Sellers will often try to save time by stripping everything down before you arrive, so that they can load you up and get you gone with minimal fuss.

This will likely also involve giving all of the dirty bits a quick rinse, so you don't try to start haggling because things are looking scruffy. This makes a degree of sense to the seller, but is the first pitfall.

You do not want the seller to give the filter a firm clean before you arrive. You want all of that lovely bacteria festering away in there, doing what bacteria do, and happily converting waste. Assure the seller that you aren't going to haggle over dirty filter media. Bully, cajole or threaten – do whatever you need to, but ensure that the filter goes untouched on the day you're coming over.

If you can, arrange to help strip the tank down yourself. For one, it'll give you a chance to ensure that nothing's wedged or forced in to place.

Ideally, you want to get the filter rigged up on to (or in, pending what kind it is) a bucket of aquarium water and keep it running. Get water and oxygen flowing through the thing, and you'll have a fighting chance of avoiding a filter crash. Let it sit stagnating, turned off and devoid of oxygen, and you'll have problems.

The filter needs to stay running as long as you're stripping the tank and catching fish. In fact, you only want to unplug it once everything else is in the car and you're ready to leave. At this point, you can either move it as is (for a short journey of half an hour or so) or open it up and remove the media (for long journeys). In the both cases, keep the media wet, but ideally not submerged. If you've got a passenger who's happy to keep splashing or dunking it on the way home, then great. Get them a bottle of wine for their efforts. Remember to take the bucket of aquarium water with you, by the way...

Once home, your first priority is to get that filter running again. Get the bucket of water inside, and get the filter on it asap. Turn it on, and get some oxygen through that thing. Now you can rig the tank up and get the fish back in without facing a major 'new tank syndrome' catastrophe. And for the love of Zeus, don't clean that media before it goes back in the filter. I can't express that enough. Once the tank has enough water in it, get that filter running back alongside the fish, right where it belongs, and with luck it'll pick up pretty much where it left off.

If you haven't got a test kit, go get one. No ifs or buts, go buy one – you just saved a load of money on a second hand tank, you cheapskate. Don't make the fish pay for your frugality. Don't rely on your local store to test it for you, you need to test every day – ammonia, nitrite and nitrate – to make sure that the filter hasn't suffered too much bacterial loss in transit.

So that's the tricky bit out of the way.

Considerations before you buy

First up, try not to pay anything before you arrive. Common sense stuff really, but forking out £500 in advance for that dream Red Sea tank (collection only), only to turn up to a disused farmhouse in Ipswich, really demoralises. And yes, it happens. I once knew someone daft enough to buy a car this way once. Never existed. And he never saw that money ever again.

Ask to see the tank running. If it's being advertised with a stock photo from an online retailer, then you should be smelling a pungent, money-hungry rat.

Here's a thing. Today, even a low end mobile phone can take a photograph that doesn't look like watercolours vomited into blender. Almost everyone who keeps fish at some point aims some form of camera at their tank to capture a souvenir shot or two. Especially if the tank is looking in any way respectable. It'd be rude not to.

So if the tank you're buying wasn't an absolute train wreck for the whole of its existence, there should be some scrap of photographic evidence to support that. Ask to see it. If it's a marine tank, you'll want to see the healthy corals and bright fish.

If it was freshwater, you should expect a plethora of colourful livestock, bursting with the vitality of their own lives. In the absence of such a picture, allow your suspicions to become raised.

Follow those suspicions. When you turn up to collect it, are there shed loads of medications in the cabinet? If so, then that suggests that the owner had issues with disease, and we all know that most disease is brought about by poor water quality. That could suggest that the filter was scrimped on, or wasn't running properly. Is it the right size for the tank? If the former owner couldn't make it work, what makes you think it'll be a breeze in your own hands?

Have a look at the silicone sealant. Often, it'll be black, which won't reveal much about the tank's history. But do have a look at it anyway. If it's peeling away, or is excessively scuffed, then you might want to rethink the 'virtually new, one careful owner' claims being made. If it's clear sealant, it should be just that – a sort of opaque whitey clear colour. If it's green or blue, the owner really has been heavy with the medications.

That being the case, be wary of any porous rock or wood on offer. Sometimes, these materials can act as sponges, sucking up medicine from the water and slowly leaching it back out. You might be getting a bargain on a whole skip worth of bogwood, but if it starts leaching copper medications out into your beloved shrimp tanks once it's back underwater, you'll regret it.

Go over the lighting closely. It wants to fire straight up, not flicker for a minute 'while it warms up'. Find out how old the tubes are. Anything over ten months and they'll need replacing soon. You can haggle over that. While you're at it, have a quick look online to see if the bulbs are still available. If it's a line that's discontinued, you'll be out of pocket. If it's LED lighting, make sure all the diodes are live. A couple out here and there indicate former problems with overheating, or an owner exaggerating how young it might be.

The filter should be as watertight as a nuclear sub, if it's an external model. Look out for and sign of scale on the edges that indicates a long term slow leak. Have a look at the seal ring inside. Is it still flexible? If it's perishing, you'll need a new one asap.

With any filter, make sure the impeller is in one piece and hasn't been botched together with superglue. Impellers are one part a hobbyist is likeliest to break, and when butchered back together, can be destructive to the impeller well. They can often be expensive to replace, too. Factor it all in.

Look into the well itself. It should be smooth the whole way down. If there are any gashes cleaved into the sides, or if it isn't perfectly round, then it may well have overheated in the past, or have been poorly maintained.

The heater should be dry as a 65 million year old fossil, too. If you spot any condensation inside, then it has had it. Don't take any excuses; a damp heater is both doomed and dangerous to you and your fish, even if the present owner says it's running fine. It'll probably set you back about £20 or so for a new one, so haggle that price.

Remember, even buying privately ensures you some rights regarding your purchase. But a key difference between buying privately and buying from a retailer is that in a private sale the goods do not have to be of satisfactory quality or fit for a specific purpose. And that's the bit we're interested in when it comes to aquaria, really.

Keep an eye open specifically for traders pretending to be private sellers so that they give you less rights than if you'd dealt with them in their trade persona. It's more common than you might think, especially when trying to offload spurious products.

The only real safeguard you have with private sales is that they need to be properly described. So, if someone tells you they're selling a ten month old LED, and you then discover that it's actually four years old (assume, say, a retailer took down the serial number, and recognises it when you take it to get repaired) then you've got a claim. If the seller says brand new, it needs to be brand new.

And this comes back to something that I mentioned earlier. Why pay a premium for new gear?

When you buy full price from a retailer, you will get a few more rights and securities than if you go second hand, and this is worth considering pending just how much damage an item can do. Take for example a tank – call it a six-foot juggernaut of a thing – which you fill up with saltwater in the front room. You come down the next morning and the front pane has flown off, and seawater has taken out your TV, stereo, electrics, Persian rug collection, and the Versace suit you had on a foot stool next to the tank. If you've bought that tank as a £50 classified ad, ten years old, don't know how long it'll last bargain, then you, sir or madam, are royally stuffed.

However, if you've just bought that from a retailer, and it's a major brand, with a lovely printed warranty stapled to your receipt from three days ago, then you might not find yourself out of pocket. Peeved, maybe, but not as poor as you could be.

I'll leave that thought with you, and wish you all the best on your Christmas purchases. And if you happen to get the urge to buy me something this year, then I'd really, really like an ADA Cube Garden tank.

Closing hint: Savvy online buyers already know, but a lot of people selling through the Internet cannot spell. When searching for something specific, try a few deliberate typos to see what comes up. You my be surprised how few other people are looking at or bidding on a 'Flaval 406' canister, or a barely used 'AI Hydar'.

Final, closing hint: Collect safely, people. If you're off to get a tank from someone you've never met, take a friend. At the very least make sure other people know where you are. Bargains are great, but you still need to be careful.