Top 10 Aquarium Myths Debunked
There’s a lot of
misinformation floating around when it comes to reef keeping. Whether passed
down through word-of-mouth or outdated advice, some myths have been widely
accepted as fact, leading many aquarists down unnecessary (and sometimes
harmful) paths. Let's separate truth from fiction by debunking 10 common
aquarium myths!
1. Bigger Tanks Are Harder to Maintain
At first glance, a
larger aquarium seems more complicated, more water, more equipment, more
cleaning. But in reality, smaller tanks are much more prone to instability,
making them harder to manage in the long run.
The reality:
Water volume plays a huge role in
stability. In larger tanks, fluctuations happen more slowly, giving
aquarists time to adjust parameters before they spiral out of control.
Small tanks experience rapid
parameter swings. A slight overfeeding, a missed water change, or a dying
coral can quickly create issues in a nano reef.
Maintenance isn't necessarily
harder—just different. While bigger tanks do require more water for
changes and larger equipment, the effort is often no greater than
maintaining a nano tank.
For beginners, a 40-75 gallon tank often provides the
best balance—large enough for stability, but not overly complex for
maintenance.
2. Clownfish Must Have Anemones to Survive
It’s easy to see why
this myth exists, pop culture has cemented the idea that clownfish need
anemones as their home. While it's true that wild clownfish form symbiotic
relationships with anemones, captive-bred clownfish don’t need them at all.
The reality:
Clownfish do not require anemones
for survival; they can live perfectly fine without one.
In captivity, many clownfish never
show hosting behavior and may ignore anemones entirely.
Some clownfish will host other
structures in an aquarium, such as soft corals, rocks, or even powerheads.
Recommended Practice:
If you plan to keep anemones, ensure
your tank is mature (6-12 months old) with stable parameters, as they are
sensitive to changes in water chemistry.
3. Corals Are Harder to Keep Than Fish
Many newcomers
hesitate to introduce corals, assuming they require advanced care. While some
species demand high-tech setups, others are surprisingly easy to keep.
The reality:
Soft corals like Xenia, Green
Star Polyps, and Kenya Trees are incredibly hardy and grow fast.
Many LPS corals like Hammers,
Frogspawns, and Duncan corals thrive in beginner setups without much
hassle.
SPS corals like Acropora can be
tricky due to strict lighting and flow needs—but they aren’t the only
coral options.
Recommended Practice:
Start with beginner-friendly coral
species that tolerate a range of conditions. Ensure stable water parameters
before attempting more delicate corals.
4. Frequent Water Changes Are Bad for Stability
Some hobbyists fear
that frequent water changes disrupt established bacteria colonies, causing
instability in reef tanks.
The reality:
Beneficial bacteria live in rock,
sand, and filtration media, NOT in the water itself. Removing water does
not harm bacterial colonies.
Regular water changes help
maintain nutrient balance and replenish lost elements like calcium and
magnesium.
In fact, skipping water changes
for too long can allow waste and unwanted nutrients to build up.
That said, some aquarists choose to minimize or even eliminate water
changes. Instead, they rely on frequent testing and precise dosing of trace
elements, carbon dosing, and nutrient export systems like refugia or protein
skimmers to maintain balance. This method can work, but it requires a deeper
understanding of reef chemistry, consistent monitoring, and a commitment to
long-term maintenance.
Recommended Practice:
Most reef tanks benefit from a consistent water change routine, such as 10–20%
weekly or biweekly. But if you’re considering a low or no-water-change method,
make sure you’re testing and dosing practices are rock solid. Either way,
stability—not perfection—is the goal.
5. You Need a Super Expensive Setup to Succeed
Many aquarium setups
on social media showcase elaborate, high-end gear—leading hobbyists to believe
reef keeping is prohibitively expensive.
The reality:
While good equipment does make
life easier, success is more about proper husbandry than expensive gear.
Many aquarists have thriving reef
tanks with budget-friendly setups that focus on the essentials.
Expensive tech is helpful but not
required—a well-maintained sump and basic filtration system can go a long
way.
Recommended Practice:
Prioritize quality over hype—invest
in reliable equipment that fits your specific tank needs rather than going for
the most expensive option.
6. You Can Add Fish Immediately After Setting Up the Tank
Many beginners
assume they can fill their tank with fish right after adding saltwater.
Unfortunately, skipping the nitrogen cycle leads to disastrous results.
The reality:
Recommended Practice:
Follow a proper tank cycling process,
testing ammonia, nitrite, and nitrate levels before introducing livestock.
7. Saltwater Tanks Are Too Difficult for Beginners
Many assume reef
tanks are only for advanced hobbyists, but that’s not entirely true! With
research and patience, beginners can succeed in saltwater.
The reality:
Many hardy fish and corals are
beginner-friendly.
Proper planning and stable water
parameters make reef tanks manageable.
Freshwater tanks have their own
challenges—saltwater is just different, not necessarily harder.
Recommended Practice:
Start with a moderately sized tank
(40+ gallons) and hardy livestock like clownfish, gobies, and soft corals.
8. Coral Needs Perfect, High-Intensity Lighting to Grow
While strong
lighting is important for some species, not all corals demand high-powered
lights.
The reality:
Soft corals and many LPS corals
thrive in moderate lighting conditions.
SPS corals need higher-intensity
lighting, but placement matters more than maxing out wattage.
Too much light can cause coral
bleaching, especially without acclimation.
Recommended Practice:
Match lighting intensity to coral needs
rather than assuming all corals need extreme brightness.
9. Live Rock Must Be Completely Covered in Coraline Algae
Some aquarists worry
when their live rock isn’t fully coated in coralline algae, thinking it
indicates poor tank health.
The reality:
Coraline algae is beneficial but
not required for success.
Live rock serves as a filtration
system, housing beneficial bacteria regardless of coralline presence.
Coraline algae grows slowly and
requires proper calcium, alkalinity, and magnesium levels.
Recommended Practice:
Rather than worrying about coralline
coverage, focus on overall water quality and biological stability in your tank.
10. Fish Only Grow to Fit the Size of Their Tank
This myth has been
around for ages, leading many hobbyists to believe that fish will naturally
adjust their growth based on the size of their aquarium. Unfortunately, this
misconception has resulted in large-growing species being kept in tanks that
are far too small, leading to serious health consequences.
The reality:
Fish do not stop growing based on
tank size, growth is dictated primarily by genetics.
In cramped conditions, some fish
may experience stunted growth, but this isn’t a healthy adaptation—it
often leads to stress, organ compression, and shortened lifespans.
Stunted fish may appear
proportionally normal at first, but internal organs continue growing,
leading to serious health issues over time.
Water quality plays a big role in
growth—high waste buildup in small tanks can suppress natural growth rates
due to stress and poor oxygen levels.
Some fish species, like tangs,
groupers, and certain freshwater species (e.g., goldfish), are often
placed in tanks far too small, with the assumption they’ll "grow only
as big as their space allows." In reality, they need large,
well-maintained tanks to thrive.
Recommended Practice:
Research adult sizes
before purchasing a fish—don't assume juveniles will remain small. Provide
adequate space for species that grow large, ensuring they have room to swim and
develop naturally. Upgrade tanks when necessary—some species may start small
but require larger aquariums as they mature. Consider tankmates carefully
crowding as aggressive or territorial species in tight quarters can lead to
increased aggression and stress.
Final Thoughts
Reef keeping is a
journey filled with learning and adapting. By debunking myths and following
science-backed practices, aquarists, whether new or experienced, can avoid
unnecessary stress and create thriving marine ecosystems.