Dinoflagellates and salinity

[Potsy]

A little more than a month ago I restarted my 50 gallon reef. In its previous incarnation, it had two very minor dino blooms that subsided on their own after a few weeks; something about the tank just didn't support large populations of ostreopsis species of dinos (identified with my microscope and the help of a microbiologist). They made a third appearance with the restart and this time they started to take over the tank. Because I only had a few gorgonians and leathers, I decided to nip it in the bud with Fauna Marin's Ultra Algae X. That did nothing to the dinos after 21 days of dosing.

So, using my microscope and refractometer, I determined the specific gravity at which this species of dinos would suffer 100% casualties and found it to be 1.014. At this s.g., 99.9999% of the dinos dies immediately with a few hanging on for a few minutes more. Freshwater kills them instantaneously.

With that knowledge, I removed my few corals, fish, and inverts to a holding tank and proceeded to lower the salinity of the display to 1.014. It worked perfectly; I couldn't find a single living dinoflagellate among the numerous samples I took.

I will next raise the salinity, wait for any ammonia/nitrite spikes, and then reintroduce the livestock after a 10 second freshwater dip, including the fish. From now on, I'm going to give everything a quick 10 second freshwater dip before its placed in the tank or quarantine so as to kill any dinos before they make it to the display. I'm not sure what effect this would have on sps but I imagine a few seconds won't hurt much.

So, I thought this would be a good strategy to use on a new,small, lightly stocked reef. I just didn't want to battle this for months.

 

[ReeferGil]

A little more than a month ago I restarted my 50 gallon reef. In its previous incarnation, it had two very minor dino blooms that subsided on their own after a few weeks; something about the tank just didn't support large populations of ostreopsis species of dinos (identified with my microscope and the help of a microbiologist). They made a third appearance with the restart and this time they started to take over the tank. Because I only had a few gorgonians and leathers, I decided to nip it in the bud with Fauna Marin's Ultra Algae X. That did nothing to the dinos after 21 days of dosing.

So, using my microscope and refractometer, I determined the specific gravity at which this species of dinos would suffer 100% casualties and found it to be 1.014. At this s.g., 99.9999% of the dinos dies immediately with a few hanging on for a few minutes more. Freshwater kills them instantaneously.

With that knowledge, I removed my few corals, fish, and inverts to a holding tank and proceeded to lower the salinity of the display to 1.014. It worked perfectly; I couldn't find a single living dinoflagellate among the numerous samples I took.

I will next raise the salinity, wait for any ammonia/nitrite spikes, and then reintroduce the livestock after a 10 second freshwater dip, including the fish. From now on, I'm going to give everything a quick 10 second freshwater dip before its placed in the tank or quarantine so as to kill any dinos before they make it to the display. I'm not sure what effect this would have on sps but I imagine a few seconds won't hurt much.

So, I thought this would be a good strategy to use on a new,small, lightly stocked reef. I just didn't want to battle this for months.

Very interesting. I have Dino only in the tank's sand bed, 75g with sump. Anyhow, I would be interested in trying an experiment and want to know what you think. If I drained my water (corals would be exposed to air during this experiment) then poured fresh RODI water into the sand bed, let it sit for a few minutes (any suggestions on time?) then pored in the same SW, would that potentially kill of the Dino? Is it worth a try?

 

[colortrilogy]

Subscribed. Thanks.

 

[TimeConsumer]

Excellent information. I battled through dinos for about 6 months a few years ago. Horrible experience, but it hardened me against fearing reef plagues and hitchhikers. Knowing that dropping the SG could have solved my problem in a matter of minutes is quite a shock. I did have success with Ultra Algae X, but it took 2 or 3 doses.

Thanks again for sharing, hopefully we can help others apply this method in the future.

 

[Potsy]

Very interesting. I have Dino only in the tank's sand bed, 75g with sump. Anyhow, I would be interested in trying an experiment and want to know what you think. If I drained my water (corals would be exposed to air during this experiment) then poured fresh RODI water into the sand bed, let it sit for a few minutes (any suggestions on time?) then pored in the same SW, would that potentially kill of the Dino? Is it worth a try?

Some things to consider:

- If they're on the sandbed, they're probably on the rock and in the sump. Perhaps they'd survive in pockets of water within the pores of the exposed rock? With the help of my microscope I was able to see that at least a few dinos were on most surfaces.

- If you pour RO/DI water on the sandbed, you'll not only kill off the dinos, but anything else that's living. This could cause an ammonia spike. I should say that I did this with a bare bottom/starboard reef with newly cycled dry rock, so there really wasn't any anything but bacteria and dinos.

I would try the traditional methods first - lights out, peroxide, pH - and if that doesn't work, you could set up a holding tank/bin to hold all livestock, and lower the salinity of the tank to hyposalinity levels for several days, while closely monitoring ammonia levels.

It's almost a reset, but not quite as denitrifying bacteria do fine in hyposalinity.

It helps to have a microscope to determine the extent of the dino die-off.

 

[Potsy]

Excellent information. I battled through dinos for about 6 months a few years ago. Horrible experience, but it hardened me against fearing reef plagues and hitchhikers. Knowing that dropping the SG could have solved my problem in a matter of minutes is quite a shock. I did have success with Ultra Algae X, but it took 2 or 3 doses.

Thanks again for sharing, hopefully we can help others apply this method in the future.

Well, now I know to dip EVERYTHING in freshwater prior to putting it in the tank. A few drops of rodi water in the petri dish under the micrscope killed them instantly.

Buying a relatively cheap but solid quality microscope ($70) goes a long way toward preventing future infestations. The other day, I bought a sinularia from a LFS and took numerous water samples from the back to view under the microscope and found absolutely no dinos. So, good to go!

 

[johnc99]

Can you describe how you determined the SG that would be lethal to the dinos? That's what I'd to know.

 

[Potsy]

Can you describe how you determined the SG that would be lethal to the dinos? That's what I'd to know.

Trial and error with a microscope, refractometer, and dropper.

 

[rustyjames]

Very interesting, thanks for sharing this.

I've had a major, what I believe, dino infestation leading me me a complete tear down. I'm also redoing my floors where the tank is,so I have to move it anyway but I'd like to eradicate these little buggers.

What are your thoughts on freshwater dip for live rock?

 

[Potsy]

Very interesting, thanks for sharing this.

I've had a major, what I believe, dino infestation leading me me a complete tear down. I'm also redoing my floors where the tank is,so I have to move it anyway but I'd like to eradicate these little buggers.

What are your thoughts on freshwater dip for live rock?

I suppose you could try that, though you'll have some die-off of desirable bacteria and micro-fauna, and there might be some nooks and crannies where the dinos survive. It only takes a few seconds of exposure, so perhaps you could do a series of dips over several days. Without a microscope you can't measure the extent of the dino's decline. It would really be frustrating to start over and find that a few stray dinos made it back into the system. But if the die-off doesn't bother you then prolonged freshwater baths will certainly kill all of the dinos. You'll have to re-cure the rock

Another option would be to do a series of peroxide overdoses in the live rock holding bin while monitoring ammonia levels. You might be able to keep your denitrifying bacteria going while eradicating the dinos. Keep a light on over the bin to monitor the dinos.

If I were you, doing a complete tear down, I'd do a bleach and/or muriatic acid bath. That way you can be absolutely sure you've eradicated the dinos, and get rid of some accumulated organics and phosphate as a bonus. I'd then restart the tank with Instant Ocean Bio-Spira to get the cycle going and shortened (a little over a week for me).


Get a 2 in 1 microscope... it'll help and beyond that there's a lot of really cool stuff to look at from the tank! I have an Omano Student Microscope bought for around $50 from microscope.com My kids and I use it all the time, putting all kinds of stuff under it. http://www.microscope.com/omano-om115-ld-2-in-1-microscope.html?category=217

Good luck!

 

[Buzz1329]

Great thread. So how did you ID that you had dino (as opposed to cyano) with the scope?

Thanks.

 

[Potsy]

Great thread. So how did you ID that you had dino (as opposed to cyano) with the scope?

Thanks.

A quick search on google images showed the signature sesame seed shape and a youtube video showed their unique manner of locomotion (spinning in circles). They're actually quite large for single celled microbes and are very easily visible at the lowest magnification. One step up in magnification and you see a lot of detail. Once you know what to look for they are very easily identified. A microbiologist at the Univ. of Maryland ("Pants" on Reefcentral) identified the species for me. While I haven't put cyano under the scope (haven't had it in a few years... knocking on wood) I would think that bacteria are too small for most hobby scopes.

 

[TimeConsumer]

Great thread. So how did you ID that you had dino (as opposed to cyano) with the scope?

Cyano looks very different under a microscope, almost like spaghetti. A reefer posted a video of cyano under a microscope on here not too long ago. I'll see if I can dig it up.