Saltwater fish and invertebrates best AVOIDED for beginners
A trip to your local fish shop (LFS) can be a very exciting experience. But … this is when you should put your wallet under lock and key until you have thoroughly researched each potential purchase.
As a newcomer to marine keeping you are often told that there are particular fish or invertebrates are best avoided until your system has matured, sometimes up to a year old.
Why a mature system?
A trip to your local fish shop (LFS) can be a very exciting experience. But … this is when you should put your wallet under lock and key until you have thoroughly researched each potential purchase.
As a newcomer to marine keeping you are often told that there are particular fish or invertebrates are best avoided until your system has matured, sometimes up to a year old.
An anemone ranks highly among those left to the more experienced and not for beginners. The reason being that anemones are notoriously difficult to keep due to their inability to cope with fluctuations which may occur in a tank of a new keeper.
Sea anemones require an extremely stable system and, as has been experienced by many, unfortunately one of the top reasons for tank crashes.
When an anemone is unhappy with its environment it will do one of two things:
It will continuously move around the tank looking for a suitable place to lodge it’s foot. An unsettled anemone will unfortunately often end up entangled in a powerhead. A damaged anemone will release toxins into the system which has the potential to kill everything in the tank.
The anemone settles, but the environment does not provide for it efficiently enough. It will begin to sag, its mouth wide open. It begins to lose its form and expels zooxanthellae. Finally it will disintegrate and release toxins into the tank, causing a crash.
There may be those lucky few enough to keep an anemone in a newer system without any trouble, but you need to ask yourself if you want to entrust the anemones life, and the life of all those within the tank, to sheer luck.
Mandarin Dragonet & Scooter Blenny
Both the Mandarin (Synchiropus splendidus) and the Scooter Blenny (Synchiropus ocellatus) are reefsafe fish that belong to the Dragonet family, and both are evolved to eat copepod.
Copepod are a small crustacean that live among the rockwork and crevices in your tank. They often become quite prolific when doing a traditional cycle, and can be seen crawling everywhere…until your first fish is added!
Copepod survive by hiding in the rockwork and emerging at night, however a Dragonet is adept at hunting them out during the day until it depletes the population.
The advice is to allow the copepod population to really get a secure footing before a Dragonet is introduced to the tank, which normally occurs when the tank is mature. To see how I feed my Mandarin fish, see this article.
My conclusion is a new system in itself can be quite stressful while you are learning the ropes, balancing elements, controlling excess nutrients, trying out the correct flow patterns and generally getting to know your system.
The decision to add a Mandarin or Scooter Blenny should only be considered once you are comfortable with your system and less stressed out by the smallest of changes.
Sand Sifting Starfish
Sand sifting stars (Astropecten polyacanthus) are first considered when a tank is fairly new and the white sand you put in begins to turn brown, which is expected in most new setups.
They are far too easily sold to beginners with the promise they will turn your sand over and eat the algae.
Sand Sifting Starfish should only be introduced to the system after an absolute minimum period of three months, and not before.
My experience is that they make no impact on the ‘whiteness’ of the sand. The sand will eventually come right as the tank matures.
Unfortunately many sifters die due to lack of anything to eat in a new system. Their diet consists mainly of detritus and the tiny creatures that live in sand, none of which are found in abundance in a new system. Without either they are doomed.
Sea Cucumbers
There are two common Sea Cucumber (Cucumaria) types sold to marine fish keepers. One feeds on detritus in the sand bed and the other filter feeds from the water column.
Much like the Sand Sifting Starfish, both require a mature system in order to feed correctly.
By googling ‘Cuke Puke’ you will soon learn the risk you are taking introducing one into a system, let alone a new setup.
Cucumbers have the potential, when stressed, to expel their innards.
This will immediately poison your entire system, causing a massive tank crash.
Once your system is mature, Sea Cucumbers are far more likely to find their food source, which in turn will minimise stress.
Damselfish
As common as these marine fish are in most local fish shops (LFS) , they have by far the worst reputation in marine keeping.
They are known to be extremely hostile and disruptive in most tanks, and are often referred to as Devil fish. Think very carefully before you buy one of these as a beginner as they are as aggressive as they are beautiful.
Six Line Wrasse
Another extremely territorial marine fish is the Six Line Wrasse (Pseudocheilinus hexataenia) that should not be introduced into a system first. The entire tank will become his domain and can result in the potential death of any other fish introduced thereafter. This fish should only be introduced as your last buy, if at all.
I know nothing about cars but a mechanic could instinctively diagnose a problem through knowledge and experience.
The ability to merely look at your system and instinctively know there is a problem, what the cause is and how to sort it out without testing your water parameters, goes a long way in ensuring the survival of the more delicate species in any tank.
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