The Top 10 Mistakes

The Top 10 Saltwater Aquarium Mistakes And How To Avoid Them


If you are new to the hobby of saltwater aquarium keeping then there will be a lot of things you don’t know yet and a lot of potential mistakes you can make.


The reason its easy to make harmful mistakes is because marine fish and invertebrates require very specific conditions to be able to survive outside their natural environment.  Basically we are trying to mimic the exact conditions of the huge tropical ocean with its massive buffering capacity in a comparatively tiny closed system (our aquariums).


Marine life has evolved in a very stable environment so has very limited ability to adapt to changes in its water conditions which occur if we make mistakes.


I want you to succeed and get as much enjoyment from your hobby as possible, so here are the most common mistakes I have encountered and how you can avoid them.


1. Taking things too fast

This is probably the number one mistake that causes new systems to crash and marine life to perish. When setting up your marine aquarium it is so vital to go slow to prevent overloading the system especially when it comes to biological filtration.


It’s very tempting to add marine life when the water is in the tank but you must be patient and give the appropriate bacterial populations time to build up to levels that can cope with the biological waste that will come from your marine life.


A tank must be properly cycled before you put any life inside, do the appropriate tests to ensure the water parameters are 100% correct.


Patience is required for just about everything you do with a saltwater aquarium, it is a living ecosystem that can only adjust gradually to new inputs so go slow!


2. Marine life incompatibility

The bottom line here is that you must thoroughly research every species you put into your aquarium to make sure it will get along with everything else you plan to keep in there.


If not it may cause stress, injury or even death.


The first consideration is not to put predatory species in with something they might like to eat; this is an expensive way to feed! Also if you plan on keeping corals and other invertebrates you will need reef-safe fish that will not eat coral.


Some species are very toxic or territorial as well which may not be agreeable to the rest of your inhabitants. Yet other species like some Tangs cannot be keep in groups, as they will constantly fight.


You will need to research potential pets eating habits, behavior and personality to make sure that they will fit in well into a harmonious happy aquarium. Choosing compatible species will save you a lot of trouble.


3. Poor water circulation and filtration

Do not underestimate the importance of these two ingredients of any healthy marine aquarium.


Ultimately it is hard to have too much of either. Poor biological filtration will quickly result in the demise of your marine life.  You need to ensure that the filtration is adequate for the bioload and is a good quality product.


Mechanical filtration is also important to keep on top of especially with a good protein skimmer.


Good filtration results in good water quality that will never build up to levels toxic to marine life.


Water circulation is needed to stir up detritus, feed/clean sessile invertebrates, increase dissolved oxygen (DO) levels and reduce algal build up.


It has also been proven that fish in high water movement environments are happier and healthier.


Ensure you have at least 2 powerheads creating multi-directional water flow unless you have a tiny aquarium.


4. System Overload causing New Tank Syndrome

This commonly occurs in a tank that has been recently cycled or has not quite completed the cycling process.


It happens when you put in too much livestock at once throwing out the delicate biological balance where your beneficial bacteria can no longer keep up with the organic waste levels and ammonium and nitrite build up.


It can happen in established aquariums too. Once again the key is to go slow. You must also be careful to preserve the bacterial populations and not accidentally physically remove them by messing with the filter media too much or damage them with some sort of fish medication for example.


5. Knowing nothing about your new marine pet except it looks pretty

This happens far more often than I can believe; people get lured in by the colors or way it swims around take it home and wonder why it dies when they don’t even know what it is!


You need to know as much as you can about any living purchase you want to make. Research what it is (if the fish store can’t tell you the vital info then move on to the next store), what it eats, what habitat it prefers, how to care for it, how hard it will be to keep with your level of experience and how compatible it will be with your other marine life.


To avoid disasters with your marine life every purchase needs to be well researched and thought out. Think of the bigger picture (your aquarium eco-system) rather than individual purchases that catch your eye.


6. Choosing sick marine life

You will need to observe your prospective pet thoroughly before you buy it.


Choosing a sick individual could easily result in its death with the shock of moving into a new aquarium, not only that but you could spread disease to your existing marine life.


The major thing to ask at your local fish store is to watch it eat, if it doesn’t display a healthy appetite and isn’t competitive in getting food DON’T buy it.


You will also want to observe its body for physical damage and parasites. Ensure it isn’t exhibiting odd behavior and that the eyes are bright and clear. Its coloration should be vivid and not faded looking.


It is very important to be able to recognize signs of stress and illness when selecting marine life this will save you money and frustration.


7. Incorrectly diagnosing disease

If you are not sure what the disease is and you medicate incorrectly chances are you could be too late and you sick pet will die.


You will need to get up to speed on marine life disease and symptoms; the Internet is a fantastic resource for this. A careful eye for detail is needed here.


For example one of the most common marine fish diseases is saltwater Ich that can be caused by one of 3 different parasites which all are treated by different medications.


But there are easy ways of finding out which organism is responsible which will allow you to act before it’s too late. Once again you need to do your research.


8. Too much medication

It’s way too common for me to hear reports about aquarists submitting sick animals to ludicrous amounts of the wrong medication in panic.


This is the wrong thing to do.


You need to identify the disease correctly then select medication that targets this disease specifically (but this said you can get really good broad spectrum solutions) and medicate according to the instructions.


Preferably this should happen in a quarantine tank to isolate the disease in a stress free environment for the patient. A Quarantine tank will also prevent the ill effect of medication damaging your other marine life, for example medicines containing copper are very toxic to corals.


9. Poor aquarium maintenance

If you let the marine aquarium chores get on top of you, you could easily throw out your water quality and cause a massive system crash that can easily be fatal.


The best way to prevent this is be disciplined and have a regular maintenance schedule with daily, weekly and monthly tasks, log them in a journal and do them religiously.


If you break tasks up in this fashion they are less likely to get on top of you. Also learn to love your maintenance; everything you do here is helping your marine life flourish. If you can’t learn to love it outsource it!


10. Filling your aquarium with poor quality water

Tap water contains varying levels of heavy metals, phosphates and other chemicals that marine life especially corals just will not tolerate.


Taking shortcuts with this can only end in tears. Purchase a RO filter unit or buy filtered water or premixed saltwater to avoid kicking yourself when it all goes wrong.