|Minimum Tank Size||Variable, See Feeding Section|
|Water Parameters||72-78 F, pH 8-8.4, Salinity 1.020-1.025|
|Aggression||Aggressive only to other blennies|
Scooter Blennies are the best introduction into the world of mandarins. The way they hop about the tank, pecking at rocks, sand and glass alike is always fun to watch. Better yet is when they take to the skies, letting out a big roar and flashing their flags at nearby fish or humans.
Blennies will spend all of their time hopping about on the substrate, live rocks and glass looking for copepods. Unlike other fish they do not make territories and will roam the entire tank. Overall they are bottom feeders.
Feeding & Diet
Feeding scooter blennies is the only difficult part of ownership. Scooter blennies are slow hunters whose diet consists of copepods and amphipods, nearly microscopic crustaceans that live in live rock and macro algae. ‘Pods’ will repopulate themselves if given enough space and time, however this requires large tanks, the use of refugiums or adding more pods frequently. This means if no target feeding is done each mandarin/scooter blenny will need a 50 gallon with sump set up or 100 gallon tank. Blennies in smaller tanks will quickly wipe out the entire pod population. Blennies are also able to eat small invertebrates such as new born shrimp, snails and crabs.
Before buying a scooter blenny it is best to have the LFS feed them in the tank. If they accept frozen or prepared foods then they may be kept in smaller tanks. However these fish are still part of the dragonet family and will not always accept other foods.
To feed scooter blennies frozen food you will first need to get them comfortable with whatever tool you will be using. The most common tool is a turkey baster. Once they stop running on sight slowly move the baster closer until it is a few inches from the blenny. Next release a single piece of food and wait for them to peck and eat the food. Continue feeding until they are no longer interested.
Note: Other fish will steal this food. Feed them right before feeding your blenny for the best results.
For picky blennies you can try introducing brine shrimp first, the most preferred frozen food by blennies, then move to blood worms and finally mysis shrimp, the most nutritious of the three. This has always given me the best, most consistent results and allowed to keep two blennies well fed in a 10 gallon tank easily.
Remember there is almost no way to over feed the scooter blenny. If they are still accepting food you should continue feeding them. The blenny can go on random hunger strikes, making it important to keep them as big as possible. They will typically stop eating on their own after only a few shrimp so there shouldn’t be any worry about over feeding the tank or fouling the water when target feeding the scooter.
Blennies are peaceful, painfully oblivious fish. So much so I can actually pet one of them before they mind my presence. However when they first spot another blenny, male or female, they will assert dominance. This will mostly consist of them coiling their bodies close to the other blenny, scooting closer and flashing their dorsal fin as they do so. If neither runs away one will bite the others tail and continue to harass them.
If they are opposite gender this will end and the two will coexist in peace. Additionally different species will often ignore one another. When keeping multiple scooter blennies you will need 2-3 females per male to avoid aggression.
Breeding & Sexing
Male and female blennies will look identical until they loose their roar. Males will have a large front dorsal fin as pictured above. Females will have a much smaller “flag”.
A female scooter blenny with small fins
To breed scooter blennies you will need more precise Conditions.
- Temperature of 75-80 F
- Salinity 1.024-1.026
- pH 7.7-8.3
- 0 Ammonia/Nitrite
- Near 0 Nitrate
- >1 Phosphate
- Frequent Feedings
- Frequent Water Changes
- Sand Substrate
First the scooter blennies must be well fed and stress free. They will not begin the mating dance with any aggressive fish nearby. when the male and female have grown comfortable with one another they will begin courting. This is easily noticed as they will swim together, often touching or locking fins.
To begin breeding the scooter blennies will meet on the floor of the tank and begin swimming upwards, keeping their bodies close to one another, gyrating and locking fins as they do so. Before they reach the surface the mandarins will split up and return to the floor. This can take place several times before any eggs are released. To finish the mating ritual the blennies will release their eggs and fertilizing materials at the end of one of their ‘rises’.
Mating will often occur 30 minutes before or after lights out. Once the spawning has finished it is essential to gather up as many eggs as possible before other fish come to eat them. The eggs have a high survival rate when placed in a device known as a kreisel. In essence it is an incubation tank that keeps the eggs suspended in the water without harming the eggs. It also keeps the water extremely clean.
The eggs must be kept between 74-79.5 F and will hatch between 12-16 hours after spawning. After 36 hours the blennies will absorb their yolks. After this point they must be fed using small foods. The foods I have had the best success with are Omega 3 brine shrimp, Hikari enriched brine & mysis shrimp. Other studies have shown Cyclopeze and piscene energetics also work extremely well.
During this time you must preform excessive water changes to prevent the excess food from fouling the water. Unlike copepods blenny larvae cannot live in dirty water. 20-50% water changes each day are highly effective, but can quickly drain your food supply. Be sure to not run out as larvae will not accept other foods.
After the larvae have grown, begin feeding them a mixture of pod. Tetraselmis, Nannochloropsis work well when paired with Prymnesiophyte Isochrysis. Continue to feed them until the reach maturity. They may be introduced to the tank as small as 1″, however with even remotely aggressive fish, such as clowns, it is best to wait until 1.5″-2″ before introduction. Remember to drip acclimate and slowly adjust the temperature. This is best done with no light to reduce stress.
- Scooter Blennies are often the target of bullies. Keep them only in peaceful tanks
- Scooter Blennies sleep buried in the substrate, often with only their eyes above ground