A lot of newcomers to the hobby rely on advice from the guy in their “local fish shop”. They often report back that their LFS guy said that they could have this fish or that invertebrate, or that they needed to buy this gizmo or use that medication.
Now whilst there are genuine fish shop guys who do know what they are talking about, and provide correct and genuinely helpful advice, there are, unfortunately, those who don’t. At the end of the day they are in business and out to make money.
So how can you make sure you’re doing the right thing?

Learning the value of research, the hard way!
With the wonders of the Internet it is amazing what information you can find online! There are many forums dedicated to marine fishkeeping, and once you join you can ask questions and help others by sharing your experiences.

My first experience of saltwater was popping into my LFS to buy some food for my pond fish and leaving with a 30-gallon tank and a book! That was four years ago. I’ve learnt a lot since then, but there is still plenty more to learn.
I thought that LFS was very good. They wouldn’t let me buy any livestock until my tank had fully cycled: great! They knew what they were talking about and were obviously experienced. My first fish? A Cube Boxfish (Ostracion cubicus). What’s wrong with that you may ask? Take a look.

Cube Boxfish
Maximum length: 18 inches (45 cm)
Minimum aquarium size: 180 US gallons (680 litres)
When stressed the Cube Boxfish can exude a toxin that may wipe out an entire tank including the boxfish itself. Because of this, if the fish is being irritated by its tank mates or near death, you need to either remove the source of the stress or the dying boxfish immediately. The effects of this toxin are non-reversible, meaning that there’s no cure for affected fish.

To summarise:
Is that the ideal fish for a beginner? No
Is that the ideal fish for a 30-gallon tank? No
Had I learned my lesson yet? Not quite. Before long I had upgraded to a 60-gallon tank. Great; bigger tank, more fish. I transferred all my stock over and went and bought some more tank mates.

Second Mistake!
Horseshoe Crab, Limulus polyphemus
Maximum length: 24 inches (60 cm)
Minimum aquarium size: 100 gallons or more
This invertebrate is barely suitable for home aquarium suitability; it is big and difficult to feed, and most specimens tend to starve to death in captivity.

So, had I learned my lesson yet? Nearly!

My next “mistake” was to buy a Cleaner Wrasse. But this time I thought I’d done my research. I read my one and only marine fishkeeping book, and it revealed the species was small and didn’t need a big tank:
Cleaner Wrasse, Labroides dimidiatus.
Maximum length: 4 inches (10cn)
Minimum aquarium size: 30 gallons
The book did go on to mention that the Cleaner Wrasse is far more sensitive to water quality than other dwarf wrasse. No problem, I thought; my tank is well maintained and easily fits that criterion!

Anyone new to the hobby might be thinking why is that an example of bad fishkeeping. I’d looked up my fish before purchase and checked that my system matched the species requirements.
But look a little deeper and you’ll see where the Internet and having more than just one book comes in handy. I must admit I’d had the wrasse quite a while before I purchased my next two books: The Conscientious Marine Aquarist by Robert M. Fenner and Marine Fishes by Scott W. Michael.
Both of these are excellent books and both have similar views on Cleaner Wrasses. In short: most aquarists are well advised to avoid cleaner wrasses, partly because they have low survival rates in captivity, but also because their removal from the reef may deprive wild populations of valuable parasite-cleaning services.

I’ve had mine for a little over two years now, and have since upgraded to 182-gallon tank with a sump. My wrasse has a few more fish to clean, but I can guarantee I won’t be replacing it with another.

Sensible shopping
I now tend to use just one shop, and we help each other out. Yes, we’ve made mistakes along the way, but no matter how much research you do, one of the things about marine fishkeeping is that there’s always something new to learn.
But you also have to remember that just because you build up a good relationship with the store owner or a particular member of staff, doesn’t mean that everyone else who works there knows as much about the livestock you’re interested in.
One day I was talking to the young lad that deals mainly with the freshwater side of the shop but is keen to learn about marine. I noticed that there was a beautiful juvenile Harlequin Sweetlips for sale. I stated that I wish I could have one. Now he knows my tank is 182-gallons and so he asked why I couldn’t have it. I explained that they need a minimum of 200 gallons as they grow to more than two feet in length! I then pointed him in the direction of one of my favourite books and told him to revise! Needless to say that fish is now stuck in his mind.

I often hear people say that they can get away with buying a fish that will become too big for their current set up because they’re going to upgrade in the future. If you know for sure that you are going to upgrade your tank, then wait. None of us can see into the future, what happens if you need to use your “fish tank fund” on major repairs to your property, car or whatever. That nice, small fish that you bought is still going to grow and will end up becoming increasingly territorial or stressed.
Another common question I hear is: “Why can’t I have a Tang in my 40-gallon tank? The shop has six tangs in the same tank and their tanks are smaller.” The point to remember here is that the shopkeeper is not planning on keeping those fish, and neither is he providing them with a long-term home. They’re in “holding pens” ready for us to purchase and place in a larger, more comfortable home. In other words: just because your LFS does something, that doesn’t make it the right way to keep fish at home.

Dangerous comparisons
The same thing goes when you’re trying to compare your tank with someone else’s. For example: you see someone has a 29-gallon tank with twelve fish in it. Great, you think, I can have twelve fish in my 29-gallon! Stop! Dig deeper, and look at the individual tank requirements. The majority of that person’s fish require a minimum of 20-gallons.

What does that person do to maintain his tank? For a starter, he has a 20-gallon sump (therefore increasing his water volume) split into three chambers. One of those chambers is a refugium that contains:
Live Rock - The use of live rock greatly increases the bio-diversity in a tank. However, its primary purpose is to provide a home for bacteria that provide the biological filtration for the aquarium.
Macro Algae – A natural Bio-filter. Often introducing microorganisms to a tank/refugium. Macro algae absorb nutrients such as phosphates and nitrates.
Deep Sand Bed - Main benefit here being nitrate reduction.
Now take into account his skimmers (removing proteins before they decompose to toxic compounds) and filter pads (removal of many impurities).

There you go, all the work is done with extra hardware. Just add this gear to your set-up, and off you go. Not quite…
Now take into account the maintenance schedule. Daily water changes; daily top offs; daily skimmer cleaning; bi-weekly filter pad changes; and monthly media changes. Still think you can handle a tank like that? It also takes time. This tank may have been set up for many years, giving it plenty of time to settle, establish and stabilize.

Best practise
Take things slowly and your tank will flourish; rush into things and you are likely to do more harm than good.
This is an enjoyable hobby, but you will enjoy it all the more if you research and plan ahead. Decide what you want to do, make a list, and find out all the individual requirements for all your livestock choices. That way you will save a lot of time, money and heartache. There is nothing worse than losing a fish or invertebrate because you didn’t research it properly. I know, I loved my horseshoe crab; he was just so prehistoric looking!
It’s a good idea to join a forum on the Internet, or a local fishkeeping club if you can. Ask questions, share experiences, let others learn from your mistakes and vice versa.
Find yourself an experienced LFS, one you can trust. It’s not a bad idea to test them: you can always ask them if they can get you a Juvenile Harlequin for your 50 gallon tank! You know the right answer to this by now! Don’t be afraid to challenge them if their suggestions don’t make sense to you.
It’s often said that if you’re not happy, just go find another LFS, but that’s sometimes easier said than done. If there’s only one store in your area, then your own research becomes even more important.
I’m not proud of my mistakes and how many fish I’ve helped to an early grave, but I hope this will help you avoid some of my misfortunes and bad experiences. Happy fishkeeping!

1. Creating a bustling, healthy reef depends more on research than anything else (© Neale Monks)
2. Fish like these Banggai Cardinals have instant appeal; but do you have the right skills and aquarium conditions to keep them? (© Neale Monks)
3. Many fish have their pros and cons: Arothron puffers are hardy, intelligent and make truly friendly pets, but they’re also large, messy, and will eat most invertebrates (© Neale Monks)