Dinoflagellates (long)

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I'm also having an outbreak in my 20 month old system. I've had dino's for 3-4 months, ever since I added a 29 gallon refugium to my 37 gallon reef. Too much water for my CPR BakPak to skim, I believe. I'm saving for a better skimmer.

Anyhow, two of my fish, a flame hawk and a yellow tailed damsel (good riddance!) died last week. Is it possible the dino can kill a fish if it is eaten?

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Hi Gary,

Oh this stuff sucks.I fought this stuff for over a year and lost.I lost a lot of corals and some fish and almost quit the hobby.

I read Dr.Ron's article in AFM and he called it snot algea and that discribed it well.I conversed with him and even sent him a sample and he confirmed it was dino's and his recommendations where to do two 50% water changes and add a booster kit to the sand bed.

Well my tank was a 200g and I already was tired of the fight.I was using a 2" aragonite sand bed.I decided to start over and set up a 55g with a DSB using HD sand.I use macro algea to aid in nutrient export.I think this DSB and all the critters are the reason it has worked.Plus alot more current.

Dr.Ron has some links to good info on these things.They are organisms and some are photosynthetic.They utilize excess nutrients.
Did you ever hear of the red tides on the coasts that kill everthing,if I remember correctly,these where dino's.

Maybe you can set up a temp tank to put you inhabitants in and then add some sugar sand to the aragonite and add a few detrivour kits and step up the water changes to your main display.

I have been suffering with a bad case of dinoflagellates (bacteria?). It's that loosely attached slime-algae-looking stuff that is covered with air bubbles and coats everything. The infestation got rather advanced before I realized I had a problem, rather than a bunch of air bubbles on things. I have been fighting it for several months and can't get it eliminated.

Here are the particulars:
120-gal. reef with all parameters as they should be. 800 W of VHO and MH light. I use B-Ionic daily to maintain alk/calcium. I perform a 15-gal water change every 4-5 days (IO with DI water). I have good coralline algae growth and essentially no hair algae. Aquarium contains a scopas tang, hepatus tang, lawnmower blenny, anemone with percula clown (1-ft. dia. that I've had for 3 yr.), sally lightfoot, two cleaner shrimp, several sps and lps corals, xenia weeds, and some mushrooms.

What I've done to combat the dinoflagellates:
Increased water changes to every other day for a month, while blowing all dinoflagellates off of rocks with turkey baster daily. Had little effect. Now back to every 4-5 days.
Started vacuuming substrate as much as I can with each water change. Again, little effect.
Upgraded skimmer from RSB to ReefDevil III with Mag 7 driving. This reduced the problem considerably, but didn't eliminate it. Skimmer has been working for about a month.
Replaced year-old VHO tubes about two weeks ago (they were about a year old). MHs are less than a year old (250-W Iwasaki 6500). No noticeable effect.
Started filtering with carbon, in addition to skimming, a couple of days ago.

The dinoflagellates still show up in spots on the rocks within 24 hr. of removal, but rock coverage has been reduced by 80%. The substrate (aragonite) is still covered within 12 hr. of cleaning.

Any suggestions on how to completely eliminate this problem would be appreciated.


Some items for your consideration, with no guarantee of success:

1) Where do you get your water? Is it phosphate and silicate free?

2) Force the pH very high (I think I read in D&S to around 8.6) for a couple of weeks. Cut back on your lighting during that time (maybe even go without lights for a few days - the presence of the corals make this tough, so watch them closely).

3) Talk yourself into pitching the old rock and substrate for new. The night before the new stuff comes in, the dinos will miraculously disappear.

Good luck, James.
I too had this problem on my 55 about 6 months ago and i sympathize with you completely. Didn't know it was dinos at the time, and I do believe it was the reason for the demise of my two blennies which I bought to control it--each died mysteriously and within days of purchase (they were purchased separately, one replaced the other).
Although not knowing exactly what started it and how I eliminated it, it's hard to pinpoint. However, it seems as though you have all the bases covered with decent make-up water and an above par skimmer.
What i did noticed once was that you have to remove all the dino from a particular rock--turkey basting will help, but you may have to toothbrush the vicinity to reomove it completely. I turkey basted for weeks, and it got so expensive with salt that I used a fine meshed net and filtered the dinos out of the water and replaced the water.
That being said, i believe you are on the right track. I would have went so far as to say that I thought it may have been only an algae 'stage' for you, but it seems as though your tank is over a year old and should be done with stages, especially with coraline growth present.
Bottom line, I suppose, is that you may have to wait it out. It seems as though you're doing everything right; I don't believe dinos are photosynthetic so I'm not for sure if decreasing lighting would help--i didn't decrease lighting and at the time I only had 160 watts of NO.
So best of luck and give it a little time.
Keep turkey basting--it's your only salvation from that streaming, snotty gunk.

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I experienced this awful mess last fall so I keep this list of tips that helped me. This is a prior response:

"I this Dinoflaggellate problem also a couple months ago. It was a light brown/tan mat of slime, with tons of tiny air bubles, covering substrate and glass. It formed long goopy strands. It blew off the rock easily. It was way worse at 6 p.m. and would seem to subside overnight, but return with a vengeance every evening. It would cover things in a matter of minutes. Sound familiar?

In my case PH would rise every evening to 8.6 evening, but I also had low alkalinity (High ph was probably caused by the daytime photosynthesis of the bloom (ie, lower CO2, higher Oxygen). Surprisingly nitrate had consistently tested very low on Salifert.
My tank was six months old, 75g, open tank, 175w mh (5.5k) with actinics, no sump, 80lbs
live rock, and 4" aragonite "sand" bed, no plenum. Very little life in the "sand" as I
seeded it with on 3-4 lbs live sand because I thought live rock would seed it over time.
I thought a CPR bakpak would be enough given light bioload and 80 lbs live rock.

Anyway - there is the background and hear is what I did to finally lick this problem. I
listed them in a possible order or importance in my case.

1. I upgraded my skimmer from the weak CPR Bakpak to a Turboflotor 1000 HO from Aqua Medic. Better skimming was very important.

2. Simple water changes and blowing it off the substrate (rock, sand, and glass) were
not enough. Water changes are important, but I finally got wise and did direct siphoning
of this gunk off the substrate with a 1/2" tube. Siphon the junk out of your tank into a
bucket. Don't just swish or blow the stuff around in the tank or simply do a water change - You need to suck this stuff out!. This also was very important.

3. I boosted alkalinity to recommended levels and resumed dosing kalk. I had made the rookie mistake of stopping kalk and alkalinity maintenance for fear my ph would keep rising beyond 8.6.

4. Use activated carbon. I used Kent at first and then switched to Two Little Fishies
Hydrocarbon II - probably doesn't matter which one though. I used a little Kent
Phosphate Sponge also.

5. I used a temporary mechanical filter (Aquaclear 300) to filter out the gunk which was stirred up and/or suspended in the water column.

6. I cut the photoperiod back on 175w mh to 4 hours a day.

7. I cut back on feeding a little.

8. I drank booze and prayed for patience.

These worked for me and my tank finally cleared up - crystal clear. I have since added a sump and a new improved sand bed, but these came after the problem had already
started cleared.

I think adequate skimming and direct siphoning of the gunk out of the tank were the key. I also believe that a truly live sand bed would have helped avoid this problem (Dead aragonite "sand" bed was a detritus trap)."

Good Luck!
If you have a "dead" sand bed then vaccum it where the dino's are the worst, this along with the added skimming and raise in PH should help ALOT. Definatly cut back on the feeding as well.


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i to have had this problem. i think the argonite reef sand\plenum was the culpret.

since removing the plenum instaling h.d play sand tank has never look better!

i beleave if you don,t have proper sand it become,s a oxgen drag on the sytem as well as a nutrent factory just like the wet\dry sytem,s.

this may be what,s going on in your sytem.

rinaldi hit the nail on the head good reply!

best of luck to you i know this can be a real nightmare. del
Gary......you are on the right track. I would suggest you start dosing Kalkwasser ASAP. This was what helped me the most, in addition to siphoning it out.
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