Strategic fish buying

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Oct 14, 2011
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Eastern Canada
Buying a fish is like going fishing - it takes time. So here are the rules of fish-buying that I learned from the old timers, quite a few years ago. I don't always follow them, but when I do, it pays off. I'm hoping this posting will add some wrinkles to a similar one from a ways back, one that has vanished into the pile of the internet.

1. It's not the cycle that kills most newly arrived fish. It's the effects of shipping. Stores have an interest in shifting blame, so since about 20 years ago, deaths are blamed on the cycle. Certainly, a bare bottomed, uncycled tank with a sudden fish load is a recipe for carnage. But let's assume you have a reasonably cycled tank with a substrate and live plants.

2. Ask when the fish you like arrived. A bad store will be delighted to say they just came in, as a bad store has to sell them before they kill them. A good store often won't sell fish for days after they arrive. A poor quality store around here had a guy who bragged about getting incredibly cheap fish from Asian farms, but informed me no fish could live for more than 10 days in any store. Uh huh. He told me "I have 3 days after arrival before these guppies start dying. Always. After that, I sell a test kit and duck." That store is no more, but that clerk is still in the trade. He's probably been cloned.

3. Study the fish. Does it look right? Then go home empty handed. Look the fish up. What are its needs? Will it work with what you have? If you're in a learning mood, check out common diseases. Study the images. Become informed.

4. The next one is easier said than done. I'm an urban creature, and grew up in the heyday of the hobby. I could walk to three quality stores in my neughbourhood. Since things went corporate, that's harder, and a lot of of us who don't even live in rural places have distance to cover to get to stores. But if you can, go to the store when it opens. Cheap stores don't pay someone before hours to remove the "deads". Because of shipping losses, there are always some, but if there are corpses littering the floor of the tanks, that gives info you can use. Never buy from a tank with even one deformed (a fish tb symptom) or sick fish. Dead fish? Use your judgment.

5. Wait a week. Yes the fish may sell. But it could go to an impulse buyer who will be busy pulling out test kits and corpses without realizing he/she bought sick fish.

6. If the fish fits with your water, and tank size, if you are not overstocked, if you know the social needs of the animal and if it looks healthy, buy it. Stay by the tank while it is caught, to get the individuals you want. Never ask someone to get you a fish while you play with your phone. Be there.

7. If you go back and there are new fish you want more than the ones you researched, start all over again. If they weren't there a week before, they are new arrivals.

8. There are great stores, but they aren't run by stupid people. I was taught these basics by the owner of an aquarium store. He appreciated quick sales and quick turnovers, but he had a reputation and he would tell this to new customers. That way, if you bought a fish on first sight (love happens...) you had been warned (divorce happens...). His fish were excellent, and suppliers feared sending him any sick fish. He was a tough old sailor and could be fierce. But he didn't ask you to blindly trust him.

9. Never rescue a sick fish. It hurts to walk away, but fish have very complex bodies and we have access to very primitive medical care for our fish. Do you want to risk bringing in a bacterial disease that will outlive the fish and infect new arrivals for years?

10. Once you become a regular at any store, you can drop your guard a little. No store wants to rob you for a $3.99 fish. It's just that many stores want to underpay their staff and have a high turnover as a result. Corporate chains drive prices down, and fishfarms cut corners to survive. Look around. If an independent store is a mess and the fish look bad, it's a 'guppy mill'. If it looks good, going back lets you start to know some interesting people working there. It is a buyer beware situation. If you buy fish online, read the reviews of the place critically. You don't want the cheapest place if they remove 194 corpses from a tank and sell you the 6 still alive. Buying sight unseen is very risky. I can do it because I have been around the fish business in my country for decades, and I know reputations (and sellers). Not everyone has had time to develop a network and gain insight into how suppliers work.

There are other things. Float the bag to equalize temperatures, but pour the water and fish through a net into a separate container. Dump the fish from the net and put the water in your house plants. Stores are crowded and diseases in the water are possible, so keep that water out of your tanks. The store fish may have immunity from contact, but your fish may not. Wild sourced fish from sustainable local fishers are infinitely healtheir than anything off a farm. Do not mix them as wild don't have the immunity to diseases any living farm fish has needed to develop. Drip acclimation leaves the fish in bad water longer, and in my experience, is serves no purpose.

Quarantine is essential, and very rare. If you have a fully cycled, spacious enough tank to keep new arrivals in, go for it. Please. Tomorrow, I will be checking stores in a city 4 hours away, and if I see what I want, I'll have to buy it without following safe fishbuying. I have QT tanks at the ready, and those fish won't get near my established fish.

You may lose a percentage of delicate fish anyway. If you want six, buy eight. This brings me around to another problem - stocking. Calculate how many fish you can keep in your tank, using all the online tools available. Then NEVER pass 75% of that. If you are right up against the maximum number, you are inviting disease to bring the numbers back down.

You might get the image of the fish store world as a scary place from this. The idea is to avoid the worst case scenarios. I have had fish for 55 years, and 90% of my purchases from stores have gone well. It's that 10% that ruins our enjoyment of the hobby, and enjoyment is what it's all about.
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A few more thoughts on @GaryE post

Quarantine tanks also help with the acclimatation of the fish and reduce the deaths associated with new fish simply because they slow the acclimation process down making it easier on the fish. Making sure the new fish has time to adjust to all the changes it goes through from the wholesaler to where you live, they just don't have the energy to all of a sudden establish their position in the existing tank's hierarchy. When are you at your best?, typically when you are well rested not when you have full on jet lag. When do you get sick?

Research your water and remember it, then research the fish you want to keep. Do the fish fit well with your typical water parameters or are you pushing the limits a bit. Do the new fish fit well with your existing fish? What kind of care do the new fish need? Before going into a fish store, you should know by heart the GH/KH, pH, and temperature you maintain, or can maintain if you are setting up a new tank. If you want to push the limits with a unique fish consider that means constant vigilance, either adjusting the water parameters, food, or some other aspect to make the fish you choose fit your system, do you have the energy to maintain this effort, what happens if you tire making the adjustments. As mentioned by GaryE take time to assess the fish you see in the store if it has caught your interest. If you know your water and the fish you own well you can always go for a coffee and research the fish you are interested in these days, all without packing a tome on fish with you.

Consider every addition changes the social dynamics within any tank. Sometimes the result of these changes affects the established fish as well as the new ones. In the worst case, a new addition will change the status of your more dominant fishes leading to a re-establishing of the social order sometimes leading to major discord in the tank, and all the problems that come from that discord.

Sometimes it is best to consider looking at the fishes in the store like you look at animals in the zoo. Go to the store without the expectation of buying a new fish but simply to look at what is interesting. Next week there might be something else interesting. I don't know of anyone who has the resources or time to own all the interesting fish they may see, and life become a bit simpler when you are no longer chasing the latest and greatest. If you want to support the store buy something to help you maintain your existing fish.

Most of the strategy buying fish, in my opinion, is mostly knowing when not to buy fish. Consider most fish live for 5 to 10 years, if you buy the fish you are committing yourself to that many years of care.

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