HELP! Midas Blenny being SUPER AGGRESSIVE in 90 gallon

Spork3245

New member
New Midas Blenny (one week in DT) just bit off part of my Fairy Wrasses tail, and then did the same to my Flasher Wrasse. He's also bullying the heck out of my cleaner goby.
The Wrasses are NOT SMALL, the Fairy is a nearly full-grown Rose Band and the flasher is a Royal Flasher.

What is going on? Midas Blennies were said to be peaceful when I asked for additions for my 90 gallon and were considered peaceful tankmates for my fish on all research unless you put them in a super-small tank (under 30 gallons). I do not want an aggressive fish - why is this midas blenny acting like this? I have over 100lbs of live rock and my tank is 3x the recommended size listed at live aquaria.

The wrasses swim NO WHERE NEAR the Midas Blenny's den/hole. The Blenny literally swam out to the top of the water column on the other side of the tank and then started attacking the wrasses for no reason.
 
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Midas Blennies are known to harass smaller fish that occupy the same ecological niche, so that's probably what is going on. Midas Blennies are planktivores, not herbivores/detritivores like most blennies. Sounds like he needs a timeout. Do you have an acclimation box? They can be used to curb aggression as well as introduce new fish. It worked wonders for me when my Exquisite Wrasse was endlessly harassing my Blue Flasher when I first introduced him.
 
Midas Blennies are known to harass smaller fish that occupy the same ecological niche, so that's probably what is going on. Midas Blennies are planktivores, not herbivores/detritivores like most blennies. Sounds like he needs a timeout. Do you have an acclimation box? They can be used to curb aggression as well as introduce new fish. It worked wonders for me when my Exquisite Wrasse was endlessly harassing my Blue Flasher when I first introduced him.

Shouldn't they be listed as semi-aggressive then instead of peaceful?
How long should I keep him in the acclimation box?
 
I have what most would consider an over stocked 40b. My Midas blenny is a model citizen with all of my fish and is BFF's with my Cherub Angel.

I have a mix of fish that occupy many levels of the WC but none that are bottom dwellers. Here is what's in my tank.

Midas Blenny
Cherub Angel
Pair Mocha Ocellaris Clowns
Royal Gramma
McCosker's wrasse
Yellow Candy Hog Fish (just added Tuesday)

The only aggressive fish in my tank is the Cherub Angel. He mostly charges my McCosker's wrasse and on occasion he will charge my female Mocha, nothing bad just more of a terrorist attack LOL. When I added the Yellow Candy Hog Fish both the Cherub Angel and McCosker's wrasse were non stop attacking him, until he found a hiding place in the rocks. On Wednesday there was still a good bit of attacking anytime the Hog fish came out of hiding. My Midas blenny was more or less trying to help out the Cherub Angel by attacking the McCosker's wrasse, but still nothing like what you're saying.

Yesterday there was still a little aggression between the McCosker's wrasse and the Yellow Candy Hog fish, today everyone is getting along great.

How big is your Midas Blenny? I'm in shock that yours is doing this and I feel bad about recommending them but honestly mine isn't an aggressive fish. The worst thing he does is pick up my scarlet legged hermit when it comes too close to his rock and his home hole and drops it off away from the rock on the sandbed. This actually happens a lot for whatever reason that hermits loves that spot.

I'm actually in shock from what you're saying. :(
 
At my LFS the Midas blenny from their display tank was in time out because he was so aggressive to the point of biting an employee that was cleaning the glass.
 
Midas Blenny is from Diver's Den. Seems full grown, bigger than even my 3+ year old Diamond Goby.
What is the best way of capturing him?
His hole is partially under another rock btw.

He stays far away from my net thus far.

Also, this fish is far more aggressive than any one I've owned, including a red headed solon fairy wrasse and a flame angel.
 
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While trying to net the Midas Blenny, my Foxface went to his favorite spot in the tank where he always hangs out while my hands are in the tank or when doing water changes, this spot happens to be right over top of the Midas Blenny's hole. The Blenny was trying to scare the Foxface away and my Foxface literally just rammed into the side of the Midas Blenny, the Midas Blenny came back around and my Foxface bit the Midas Blenny. Seriously.
My Foxface is the most gentle fish I've ever owned and tries to swim with everyone, and the Foxface is actively attacking this Midas Blenny when it tries to bully him. This Midas Blenny is psychotic and part of me wants the Foxface to sting him. When I catch this Blenny he's going for up for sale on the NJ Reefer's Club, $30, bring your own bag and make sure you have fish that don't take crap.

BTW - Still no luck netting him. Tips would be wonderful.
 
Not surprised the foxface is trying to put the blenny in its place. They are gentle fish, but they don't take crap from other fish. :)

As far as trapping the blenny, I've had great success with the AquaMedic fish trap: http://www.bulkreefsupply.com/aqua-...KHow1CD5pzRsth8elVSwv5Neks1TNdm6frxoCcGzw_wcB


I have a similar one: http://www.amazon.com/SaltwaterAqua...UTF8&qid=1458434282&sr=8-5&keywords=fish+trap

I've yet to use it. what's the best way to do this? Put some food in it and wait for the blenny to go in as opposed to the other fish?
 
I've yet to use it. what's the best way to do this? Put some food in it and wait for the blenny to go in as opposed to the other fish?

Pretty much. The one I have has a special feeding tube that makes it easy to feed inside the trap. When trapping a fish, you'll need to get them accustomed to the trap being in the tank, so it usually takes a few days of feeding inside the trap for them to get used to it being there. Then it's just a matter of waiting until your target goes in the trap.
 
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