Parasitic Tegastidae copepods "Black Bugs"

[Frogger]

I just want to let everyone know that there is a Tegastidae copepod that seems to be common on acropora frags that are coming out of the Vancouver area. I have found it on the last few acropora frags I have purchased from different reefers.

This guy is not the red bug that we have all heard about. It is different. It appears to be smaller it is black with a red spot. Some call them Black bugs but there is conflicting information on exactly what black bug is.

This guy is not visible with the naked eye. With a hand lens it is still a tiny speck and really not visible. The red spot is not visible with a hand lens. In order to see it I had to pull out the dissecting scope and look at the coral frags under high power. I do not know if it is isolated to Acropora as I have not checked my other corals as it requires me to remove the coral from the tank and inspect it under a microscope.

These guys laugh at Coral RX. The only thing I have found that is effective is a Bayer dip. I am not sure about Revive or other home made remedies.

I have have had it in my display tank for quite some time. I thought my Melanarus wrasse would keep the numbers under check. I am not sure how much damage these guys cause. They seem to aggravate the corals and I have seen some decline generally starting from the bottom up and some lack of polyp extension on the corals that are most heavily affected. There appears to be about 20 of them per inch of coral when the coral is heavily affected.

I am currently treating my tank with Interceptor flavor tabs (Milbemycin Oxime). I got the prescription from my cat vet after I took in copies of several papers including Dana Riddle's article in Advanced Aquarist. I had pictures of my tank and knew what I was talking about when I explained to him what I needed. This stuff is expensive. If you can't get some from your vet you can also use the product Dr G'c Coral Dip Solution as it is Milbemycin Oxime and RO water. I just don't know the product concentration.

I have treated 2 times at the recommended dose. After the first treatment the number of black bugs was reduced substantially, after the second dose only saw a couple and they were not moving. These guys generally are very active. Will be doing third and final dose this weekend.

I have noticed a large reduction of pod population, the Interceptor does not appear to have affected any thing else, corals, fish, snails urchin. I do not have any shrimp or crabs in this tank.

I will be treating all new arrivals with bayer.

[Razor Ramon]

Wow that’s crappy. Those black bugs are tough MFs. I’ve dealt with the bigger ones that like monties and acros they are about twice the size of red bugs as well as ones I call clear bugs wich are smaller than red bugs . I used interceptor as well first time used regular dose . Killed all red bugs never to see again but the black and clear came back after about half a year . Then I did a second dose of interceptor but very strong for the size of my tank for 3 weeks . It’s strange because inseptor is for worms and crustations. But doesn’t seem to kill all of them, certain ones are tough. I still have feather dusters ,tube worms, bristle worms , and all kinds of pods ,but it did kill all red bugs and shrimp pods . Something else I found is they like certain corals and will not infest another right beside it . So if you can remove and dip weekly the little MF WILL DIE! Dipping the coral weekly and using a turkey baster and blasting them off works the best for me . When dipping I only use minimal time just enough to knock them off then use a magnifying glass with a light to look and scrape any eggs off .
Thanks again for the heads up we need look very close at our wet pets for pests and quarantine .

[Frogger]

Interceptor treatments have only reduced the numbers but have not eliminated them. I increased the dosage to double yesterday and they are still active today. Will likely triple dosage next week if no improvement. Sometimes it takes a while for the interceptor to kill them. I will leave it in the water column for a couple days before turning on skimmer and adding activated carbon.

Apparently you can go up to quadruple dosage and not adversely affect the corals and fish.

Will keep you posted. I will try to get a picture.

[Frogger]

https://farm8.staticflickr.com/7841/40376658263_c28b2ebbed_b.jpg (https://flic.kr/p/24vWVNp)black bugs 3 (https://flic.kr/p/24vWVNp) by Glenn Murray (https://www.flickr.com/photos/167567799@N03/)

Two of the bugs on acro circled. Taken with macro Olympus T5 zoomed in all the way cropped and enlarged. These guys are small

Will get better picture when I get my microscope out.

[Frogger]

https://farm5.staticflickr.com/4907/46675047744_a1ba2e57ee_h.jpg (https://flic.kr/p/2e7vPyu)copepod 1 (https://flic.kr/p/2e7vPyu) by Glenn Murray (https://www.flickr.com/photos/167567799@N03/),

This is a side view at 800 times magnification. The front end is the wider section at the bottom. For scale I believe the round ball like structures at the top are zooxanthellae cells.

[Frogger]

https://farm5.staticflickr.com/4867/40432735293_4d35636d9e_c.jpg (https://flic.kr/p/24AUkxK)copepod3 (https://flic.kr/p/24AUkxK) by Glenn Murray (https://www.flickr.com/photos/167567799@N03/)

This is a view of 4 of them seen at 60 time magnification on the dissecting scope. They seem to hang out on the polyps and inside the corallites. There is hundreds of these guys on a small 2" frag.

[Frogger]

https://farm5.staticflickr.com/4882/46483258135_eaf5474008_c.jpg (https://flic.kr/p/2dPyRc6)copepod 2 (https://flic.kr/p/2dPyRc6) by Glenn Murray (https://www.flickr.com/photos/167567799@N03/)

The red dot is the front of this guy. This is a top down view at 800 times magnification.

[Frogger]

To date I have used 2 treatments of interceptor at 100%. I did the 3rd treatment at 160%. I just treated today, 4th treatment at 240% of the recommended dosage. From what I can see I can go up to 400%.

So far the treatments only seemed to reduce the population of these copepods. It has slightly affected the amphipod population and does not appear to have had a major impact on my snails. Fish and corals show no sign of stress.

Will keep you posted. Like I said before I have received acro cuttings from many different reefers locally. I noticed it on the last couple of frags I bought which have been treated with bayer and are in the frag tank. Those frags have not set foot in my display tank.

The little buggers that I have in the display tank I must have gotten earlier. Every cutting I have has been dipped in Coral RX. Coral RX does not in phase these guys. They are just a tiny little dot with a hand lens and are really not visible. I did not start finding these guys until I was looking at them under the microscope.

[DKoKoMan]

Ugh ... thanks for all the information on this. It’s crazy how many things attach to corals which are hard to see with the naked eye. I am fascinated with the under microscope photos of these little pests. Have you figured out if they are eating the acros skin? Or just irrating the polyps? Also you may have answered earlier, but are they taking to any other corals or just acros?

[Frogger]

Ugh ... thanks for all the information on this. It’s crazy how many things attach to corals which are hard to see with the naked eye. I am fascinated with the under microscope photos of these little pests. Have you figured out if they are eating the acros skin? Or just irrating the polyps? Also you may have answered earlier, but are they taking to any other corals or just acros?

Because they are almost impossible to see I cannot be sure. Before I started treating I could see them on most of the acropora that are close to the front glass. Since I have been treating I can only see them on my colony of Shades of fall and my orange passion frag. The orange passion frag has them the worst. This is the one I am able to take out of the tank to look at under the microscope. With my optivisor on and a bright light at night I can just make out the little spots moving around on the orange passion. I don't want to treat the orange passion with bayer because if I do then I will not be able to monitor how effective the control is.

I have no idea what they are doing but they are definitely aggravating the corals and the polyps are not fully extending. In each of the corallites there are several of these guys

[DKoKoMan]

My god! These little buggers are definitely a handful. That’s the thing with the tiny size, lots of people probably have them but don’t have the skill to detect. Following along on the treatment trials. Keep up the good work as sharing is caring.

[Frogger]

That’s the thing with the tiny size, lots of people probably have them but don’t have the skill to detect.

Yes that is the reason for posting this, the last two reefers/vendors I purchased acro's from had this pest and they were not aware they had it because I told them after I found it. The black bug that is in my main display and on the last two purchases I have made appear to be the same guy, coincidence? I think not.

I was not aware of it before so I can not say who I got it from and if any corals are actually clean. I had spent most of my time doing careful inspections with my microscope for AEFW and I have seen those often as well. Coral RX works on flatworm, at least dislodges it from the coral, although every time I have found it I have returned the corals to the vendor/reefer but Coral RX has no affect on black bugs.

Most of the corals in my tank are not negatively affected as their growth is good, colours could be a bit better (nit picky). However those that have been affected are not doing great, growth has been reduced, colours are not good and polyps are not fully extended. I cannot say that any corals have died from this but I would not know as I wasn't checking for it over 2 months ago.

Yesterdays treatment: I checked last night before going to bed and there were still quite a few on the orange passion, the amphripods on the rocks did not appear to be affected. I just checked the orange passion and I can't see any black bugs on the coral (just looking through the glass with a 10x optivisor. But it is day time and they are not usually that active during the day. In the past I have always been able to see them during the day, so I am cautiously optimistic but it is way to early to say.

If it hasn't killed them all but reduced the numbers this is good because it means I am getting close to the correct dose.

[Razor Ramon]

What kind of dose pre week and what size water volume are you using now. Has the medicine killed all your crabs, shrimps , feather dusters and all your other worms, ampapods ,and copepods. Have you experienced a nitrate spike from thing die off .
I hope you find a way to kill them . Pipe fish are predators but you would have to quartine the coral with the fish and do weekly dips . Just a thought if the bugs are immune to the interceptor.These bugs are tough. Ugly to! Wicked pictures!

[Frogger]

What kind of dose pre week and what size water volume are you using now. Has the medicine killed all your crabs, shrimps , feather dusters and all your other worms, ampapods ,and copepods.

I don't have any crabs or shrimp in my main display. As of tonight I cannot see any black bugs but still too premature to start celebrating.

My amphripod population took a huge hit with that last dose I could only see a couple tonight. I have seen a bunch of dead bristle worms. Snails still active. I did a 20% water change tonight. My tank is a 75gallon redsea reefer total volume with sump 90 gallons. I am guessing 80 gallons water maybe a little less once rock is taken into consideration. I will give you a breakdown of exactly what my doses were, how often how much water change ect once I have successfully eradicated this menace.

My tank is a nitrogen sink. I have never had readable nitrates and I have to add nitrates (NaNO3) daily to keep my nitrates at .5ppm. I have not seen a change in the nitrate usage. I will check again tonight to see if that has changed after the pod population has been wiped out.

I have a melanarus wrasse but not sure if he has taken a liking to the black bug. Likely not because the wrasse is asleep in the sand when the black bugs are active.

[Frogger]

No change in nitrate

[Razor Ramon]

Thank you , for doing this thread it will be a great help with other reefers to come . You are very detailed in what you do and it’s great that you pass it on . Thanks I’ll keep following in on your war on these tough coral bugs.

[Bblinks]

Tagging along. Thanks for the detail write-up Glen.

[Frogger]

Tuesday night update. Last dosed interceptor Saturday am, did a 20% water change on Sunday pm, turned skimmer on Sunday pm and added carbon on Monday.
I am happy to say that I have not seen a single black bug since Saturday night. However I have 37+ acros (including cuttings) and I really can only see one side of about a half dozen of them. I have not taken any out of the tank and put under a microscope. Often these little buggers hide inside the corallites behind the polyps so they are not always visible. But considering on Saturday before I did the latest dose I could easily see about 30 of these guys on my orange passion. Under the microscope there were easily more than a hundred on the coral.

No changes to any of my water parameters (nitrates, phosphates, alkalinity and calcium usage).

Maybe its me but I can see extended polyps during the day on corals that normally do not readily extend their polyps and usually only at night if they do. I actually see "some" (I use that word loosely) polyps on my RR Pink Floyd. I have had the coral for almost 2 years, it has never grown a millimeter although it has maintained its colour all this time. It has been 1.5 years since I have seen a polyp on it.

Keeping fingers crossed, will do another treatment (hopefully last) at the same dosage about 2.75 times recommend on Saturday just to be sure. Copepods are either free spawners or broadcasters (females carry eggs until hatching) so I do not think that unhatched eggs are an issue, second dose should take care of any extras just in case.

[Frogger]

Friday night update. I was getting hopeful. I have been looking closely at my corals, orange passion particularly. I have been checking day and night at least 3 to 4 times a day using a pair of 10x optivisors (true 10x power). These are about the most powerful magnifying glasses you can get. Way more powerful than any hand lens. I hadn't seen one black bug all week. I started thinking maybe I got them all.

Tonight I pulled out the dissecting microscope (true 40x power) pulled the orange passion out of the tank and into a glass of water making sure not to expose the coral to the air and carefully inspected the coral looking into the corallites and between the polyps and I found 1 very active black bug. Where there is 1 there is likely more. There is also a good chance when I put the bright lights on on the microscope that the black bugs either hide under the polyps or go to the underside of the coral. So I do not know how many remain on this frag.

The good news is there were 3 to 4 of these guys per corallite (polyp) last week before I did the last treatment where as this week I could only find 1 on the entire coral.

I know my dosage is getting close. I will treat again tomorrow with a rate 10-15% higher than last week. This should hopefully be the killing dose. Unfortunately my amphipods and bristleworms will take another hit. Hopefully some will survive and re-populate the tank.

On another note I have only been able to find 1 remaining tubeworm (had hundreds before I began treatment) and the population of bristleworms is way down. Unfortunately this drug has had no effect on vermetid snails, montipora nudibranch and hydroids. I was hoping for some collateral damage.

Looks like I will have to re-seed the tank with healthy microfauna from my other tanks after the treatment is complete.

[Razor Ramon]

Hope your dose kills them all on the 4th week treatment. Too bad there is so little known on dose size and water volume. Cutting up pills int 4 peaces then guessing water and if that’s enough medicine. The medicine is time baced for potency after 8hrs the tank is consuming it trough biodiversity of the system.
These tough bug needed to be hit hard right from the first dose. But who knows
The impact on the tank or the inhabitants. Hopefully your next dose is like a rain of death to those little buggers an atom bomb you nuke them all !!! And your not breading a resistant strain of a alread tough bug. Keep us all in the loop I hope you the best !!!!

[Frogger]

Hope your dose kills them all on the 4th week treatment. Too bad there is so little known on dose size and water volume. Cutting up pills int 4 peaces then guessing water and if that’s enough medicine.


I have a very accurate scale. Each 23mg pill weighs .95mg so I have a record of exactly how much I have been adding.

Todays dose will be the 5th treatment. I have an exact breakdown of what was added and when I added based on the size of my tank. As soon as I am confident I have the right dose I will let you all know what that dose is. Even though I know I go go up to 4 times the recommended amount I do not want to go there unless I have to as I do not want to kill more microfauna then I have to.

My last dose was 43mg which is almost half a tablet. 1 tablet is supposed to treat 400 gallons per treatment. My tank is about 75-80 gallons of actual water so I should be using 19mg per treatment. At 43mg I was using 2.4 times the recommended dose.

I will be adding about 50-55mg (of a tablet) later today which would be 2.7 times the recommended dose. I have to take my skimmer offline and remove my carbon. I use no other form of filtration like GFO, carbon dosing ect. It is a good thing there are 8 tablets in a package I may end up needing them all.

What I do not know is:
How will the other treatments affect this treatment?
Does the drug build up in the system?
Does the black bug build up a resistance with the lower doses?
Does skimming and carbon remove residual drug from the water?

What I will be able to do is establish a baseline from which other reefers can treat their tanks.

[Frogger]

I just made the last dose (I hope) at .54mg of a pill. That works out to 2.8 times the recommended dose for red bug.

A couple things to note. This pill does not dissolve in water. I use a pestle and mortar to crush the pill up into a fine dust. I then mix that with a cup of RO water for about a half hour. After a half hour there is still fines that have accumulated on the side cup. I mush these with my finger (where gloves) until the fines have disappeared. I want to be sure to that all of the drug gets into the water and I do not waste any that hasn't fully dissolved.

Since I have been adding this drug to my tank film algae is growing at an exponential rate nearly 3 times faster then before on the glass.

[Razor Ramon]

Let them have it Glen nuke em!
8pk of pills that is nice my vet sold me a dose 1 pill only. That came in a box marked large dog.

[Razor Ramon]

After your findings I’ll let my vet read your write up and I’m sure he will be more prone to prescribe multiple pills to a reefers for a treatment of there tank . Your thread is much better than all out so far .
Thank you

[Frogger]

8pk of pills that is nice my vet sold me a dose 1 pill only. That came in a box marked large dog.

My mistake there are 6 in a box of Interceptor Flavor Tabs Large dog not 8. I have used 2 so far for my 75 gallon tank.

[Frogger]

It is raining bristle worms in my tank. Looks like I have hit the Bristle worm threshold.

[Frogger]

Ok it is Thursday night, my last dose was last Saturday and it is time for an update. I have been keeping a close eye on my corals looking at them closely every night and have not seen any activity. This evening I broke out the microscope and did a complete full view of my orange passion.

These little guys are really small and even with a microscope they are tough to find. They are smaller then the tip of a polyp and often hide inside the coralites making them tough to see. Tonight when I pulled out the orange passion the polyps were out a lot more than usual and seemed really big. I took me about a hour to completely search the coral. A couple of times my heart stopped because I thought I saw a black bug, however it was usually just a polyp at an odd angle. I could find no black bugs. I also pulled out a coral from my quarantine tank to give it a once over and found no black bugs.

I am going to call this a success for now and will keep you posted. It took me 5 treatments to finally get this guy. One pill is 94mg (23mg of actual drug) First 2 treatments were 20mg (1/5th) of a pill. The third treatment was 31mg, the forth treatment was 43mg and the final treatment was 54mg more than half a pill. I ended up using almost 2 whole pills for my 75 to 80 gallons of actual water. The drug I used was Interceptor Flavor Tabs as it has only Milbemycin Oxime and nothing else. I was a little worried about Sentinel or the other ones because they have other drugs. I was using fresh Interceptor expiry date Jan 2021. So there shouldn't have been a problem with drug potency.

The Good
I watch my corals closely and am always aware the first sign that something is wrong. Many of my acros currently look better than they have in a very long time. They are showing colours I have not seen and polyps are extended during the day. I feel I may be over the hump with this pest. The treatment did not effect any of my fish or corals and I am not sure about the snails because I had hundreds and I still have many.
The Bad
The drug is expensive and difficult to get. I have pretty much wiped out my pod, my bristle worm and my feather duster populations. Some would consider loss of bristle worms as a good thing, I do not follow that chain of thinking. CUC can be replaced. It took a while to get this drug to work. Coral dips like Coral Rx are not effective on this bug.
The Ugly
This pest is extremely difficult to detect. I have had this pest for a long time and it has effected many of my acros, I can't say they directly killed them but they stressed them. I am hoping that local reefers will really inspect their acros because if they do not they will just keep being spread to reefers tanks.

[DKoKoMan]

Great write up frogger! Hope I don’t get these buggers, but if I do I can refer to this.

[Frogger]

THE KILLING DOSE
I have calculated out the dosage that seemed to kill the black bugs and it is nearly 3 times the recommended dose for red bugs.

One 23mg tablet will treat 135 gallons of water.
3/4 of a tablet will treat a 100 gallon tank. This works out to 16.7mg of Milbemycin Oxime per 100 gallons. One tablet is 23mg (M.Oxime) and weighs 94mg.

As I did 5 doses I do not know if the earlier doses played any part in killing all of these bugs. You might have to do multiple treatments.

I make no promises that you will have the same success as me, it may wipe out your entire tank. I have no shrimp, crabs or clams in my tank so I do not know how these would be affected, based on the red bug treatments probably not well.

[Razor Ramon]

Thanks for the up date ! Keeping my fingers crossed for you . Hope you got them all .

[Razor Ramon]

Do you have a 2 week up date we’re you able to nuke all the wee beastys .

[Frogger]

Do you have a 2 week up date we’re you able to nuke all the wee beastys .

Ok update time. Last treatment was March 23 (3 weeks ago). I have kept a close eye on the corals and I have not seen one black bug since March 23.

The treatment was not without its problems. I lost most of my amphipods, bristleworms, feather dusters, spaghetti worms, etc. Not sure if it affected any of the smaller organisms in the tank.

Many of my acros are looking better, however my Jason Fox has taken a turn for the worse since I started the treatment my strawberry shortcake is half looking great and coloured up nicely but half of it has lost quite a bit of colour. There are a couple other corals that are not really doing great. The other 15- 20 or so acros are looking great with increased growth.

Not sure if the issues with these acros are from the actual treatment, the bugs before the treatment stressing them or recently I had my Giros revert to alternating gyre mode once or twice a day, it kicked up quite a bit of gravel covering everything with dust and making the water column cloudy. The gyre thing has been happening for the past few weeks until I finally figured out yesterday it was happening. I think I have fixed it by completely reprogramming it.

[Frogger]

7 week update. No signs of black bug, checking only once every week or 2.
Jason Fox recovering from tip dieback and loss of tissue. Other corals seem to be doing well. Amphipods and other things making a good comeback.

So it seems my last dose was the killing dose.