Top 10 Reef Tank Myths - Avoid These Falsehoods, Fabrications, and Fallacies In Your Aquarium
In a connected world where information is free and easy to access for anybody with an internet connection, it can sometimes be difficult to differentiate fact from fiction. When you consider the aquarium hobby or more specifically the reef aquarium hobby, incomplete truths, and misleading advice can set new hobbyists down a path of frustration and failure. The good news is, we won't stand for it!
Whether you're new to the reef hobby or simply set in your ways, here's a list of common myths and falsehoods that just might help you avoid a catastrophe.
1. Nano reef tanks are easier than large tanks
False - small aquariums make it much more difficult to maintain stability because of the smaller water volume. Changes in water chemistry occur more quickly in small volumes of water. For example, a few pieces of leftover food could increase the nitrate level in a nano aquarium drastically while that same amount of leftover food in a 90-gallon aquarium won't even register on your test kit. While a smaller aquarium is certainly more affordable and is easier to fill with livestock, you have much less room for error in terms of keeping the aquarium healthy.
2. Saltwater Aquariums are expensive and difficult
This isn't always the case because an aquarium can be as simple or as complex as you want it to be. It's a matter of choosing the right livestock and building the aquarium to accommodate your particular desires. Some fish and corals are much hardier or more affordable and, therefore, easier to maintain or obtain than others. If you decide to only keep a pair of clownfish without any corals, the equipment is very basic. We also have an incredible variety of all-in-one aquarium kits that simplify both the setup and maintenance of an aquarium.
3. 0 phosphates and 0 nitrates are a good thing
This deeply rooted belief that nitrates and phosphate are the enemies stemmed from early aquarists and the constant battle against nuisance algae. While these nutrients are a "fertilizer" for nuisance algae, they are also fundamental for the biological stability of the aquarium.
The complete absence of nitrate and phosphate leads to bacterial imbalances and can starve your corals of vital nutrients they need to grow. On the flip side, too much nitrate and phosphate will degrade water quality, can lead to excessive algae growth, and impede coral growth. The key is maintaining a balance where the nutrients exist at low levels and are not constantly rising. This can be achieved through active monitoring and effective nutrient export techniques.
4. If you feed your fish too much, they will eat themselves to death
Fish will not eat themselves to death, it's just not something they are biologically capable of doing. That said, excess fish food and the resulting waste will degrade water quality and if left unchecked, can wind up harming your tank inhabitants. In most cases, too much food waste will lead to discolored and smelly water quality, algae blooms, and coral stress. The water can eventually become toxic but is only a threat in the most severe cases where ammonia is present.
The trick to feeding correctly is finding a balance where your fish are getting the nutrients they need while not allowing for a rise in nitrates and phosphate levels. So long as your aquarium is cycled with sufficient biological filtration, ammonia should never be a threat.
5. Fish will only grow to the size of the tank
This is another long-standing myth that likely stemmed from the desire to put carnival goldfish in homes across America. When a fish doesn't have enough space or suitable habitat, it becomes stressed and unable to reach its full potential in terms of health. This may show in various ways including stunted growth, loss of color, aggression, compromised immunity, and in the most severe circumstances that stress can eventually lead to a shortened lifespan.
6. Canister filters are nitrate factories when used in saltwater aquariums
A canister filter can be a nitrate factory on any aquarium because they are designed to trap debris. If that debris is not removed on a regular basis, bacteria will break down the trapped debris creating nitrates. So long as you maintain the canister filter on a regular basis, it will do its job and remove debris before it can be broken down into nitrates.
Here's the catch - saltwater aquariums typically wind up with more detritus and debris floating around the tank, so it's just all that more important to maintain the filtration on a very regular basis. For example, you might be able to get away with cleaning your freshwater canister filter every two weeks while you would need to clean it weekly when used on a saltwater aquarium.
7. A pH of 7.8 is acceptable as long as it's stable
Both seasoned and novice hobbyists alike seem to adopt this false ideology around maintaining a stable pH. While stability is king and this advice does have good intentions, it's just not entirely accurate for reef tank owners.
We do agree that stability is incredibly important with pH but when you expose coral to pH levels below 8.3, they cannot create skeletal material as efficiently. This effect becomes exponentially more severe as the pH falls below 8.3. Low pH conditions inhibit the calcification process and slow down coral growth, even if it's rock solid with minimal swings throughout the day. While you can keep corals alive at a pH level of 7.8, they will thrive and grow much faster the closer you get to 8.3.
8. Ich is always present in your aquarium
Ich is not always present in your aquarium. Ich is caused by a parasite (Cryptocaryon irritans) that is introduced to your tank as a "hitchhiker" on fish, corals, rock, and even in the water itself. The life stages of Ich consist of a free swimming stage (in the water), an active stage (on the fish), and an affixed stage (on the substrate, rocks, frag plugs, etc.) meaning it's incredibly difficult to eradicate this parasite 100% when stocking your aquarium. Following an effective quarantine protocol is the BEST defense against introducing any disease into your aquarium, including Marine Ich.
Furthermore, should Ich show up, you can eliminate the parasite but it requires removing all of your fish and allowing the display tank to run fallow (without fish) for 72 days which effectively starves the parasite. Without the fish as a host, the parasite can no longer continue its life cycle.
View Playlist: FISH HEALTH AND 80/20 QUARANTINE VIDEO SERIES
9. Garlic cures Ich
Garlic does not cure Ich. It simply makes food more enticing to fish which, in some cases, can help deliver medications and maintain the health of a fish who is suffering from parasites like Ich. There is little scientific evidence around the health benefits of feeding garlic to fish yet it has long been a popular fish food additive.
10. UV Sterilizers are not safe for reef aquariums
UV Sterilizers are indeed safe for use on reef aquariums and will not harm the biological balance. Since the UV sterilizer only affects organisms that are free floating in the water column, it will not affect the beneficial bacteria that live on the surfaces of your rock, sand, and biological filter media.
In terms of microorganisms and phytoplankton, your reef will not suffer when UV sterilization is used correctly. Living phytoplankton is not naturally abundant in reef aquariums, this is exactly why we have to grow live phyto cultures separately and dose the aquarium. Turning off the UV sterilizer while you dose is recommended and your skimmer will soon remove any dead or leftover phytoplankton anyway.
Any microorganisms like copepods would only be at risk if they are free floating in the water column and since most of these organisms inhabit the substrate, there should not be any negative effect. That said, there are some beneficial pods and organisms that do inhabit the water column and these select organisms could be at risk but the negative effects on your reef as a whole are negligible if any at all.
BONUS Myth - Clownfish can only be kept in pairs
This myth still comes up from time to time, especially when stocking a new aquarium, and is rooted in the fact that clownfish can be aggressive toward one another. While clownfish do thrive in single pairs in your tank, it is possible to maintain a harem or group of clownfish so long as you stock them correctly.
Ideally, you obtain small captive-bred clownfish which typically have a much more mild temperament. They should all be about the same size, 1" - 1.5" is ideal; in many cases, you can obtain all the fish from the same group. I think the most important part is getting juvenile fish of all the same size and your chances of success will improve drastically if the fish come from the same group where they have been raised/housed together for some time. Clownfish are usually bred and kept in groups up until they are sold to retailers or grown out for broodstock and paired up.
Introduce all of those small clownfish simultaneously, keep them well-fed with high-quality foods, and provide optimal habitat. One large (8" or more) anemone could suffice for small groups, but multiple anemones are ideal. So long as they are not forced to compete for resources, the fish should thrive alongside each other as they do naturally. Clownfish naturally live in groups with the largest fish being the dominant female and the smaller submissive fish being the males. The exact size of the group varies and the point is, they don't always have to be in single pairs.