I'm starting to write up an article on this so don't worry about the length of this post. Everyone here feel free to edit the initial rough draft of this. I value your advice. I'm not convinced you have dinoflagellates but thought I would throw this out for you to look at.
Many times I have seen people worried about a film of cyanobacteria (slime algae). The helpful people post all of the proper questions to help a reefer solve their problem. I.E.---How old are your bulbs?, Do you use RO
water?, What are your nitrate and phosphate levels?, When was the last time you did a water change?, Do you have good flow in your tank?, Did your tank just finish cycling?.....
Then a week later, the same person will come back on and tell everyone that they did what they were told, and the slime algae still exists. This will start a round of questions like.....What test kits are you using?, When was the last time your RO
membrane and resins were replaced, etc., etc. They are told to do another waterchange and it will resolve itself---but it doesn't.
IF IT WALKS LIKE A DUCK AND IT TALKS LIKE A DUCK, IT IS ......
Usually a duck---but not always. Sometimes we think we are dealing with cyanobacteria and we are not. Sometimes we are dealing with dinoflagellates. Almost all of us with reeftanks, have dinoflagellates in our tank----Zooxanthellae. This symbiotic dinoflagellate is present in many of our corals. They are from the Kingdom of Protista and the Division of Dinoflagellata. This group possesses two flagella which move them through the water. They have additional pigments in addition to chlorophyll---usually brown or red. Some of them are bioluminescent. I'm sure many of you have heard of bays that glow when the water is disturbed. If you like to experiment, check out this link (BUT DO NOT PUT THIS IN YOUR REEF TANK---ONLY A SPECIALLY SET UP NANO). http://www.lifesci.ucsb.edu/~biolum/.../dinohome.html
The brown dinoflagellates are present in many of our corals and that is the reason there are so many brown corals. The red dinoflagellates are sometimes known as the Red Tide. I'm sure most of you have read at one time or another about the Red Tide destroying a reef. You do not want this in your tank. Not only do dinoflagellates exist in many corals, they also exist in many Tridacna Clams, anemones, and some sponges. They are never a problem if they are existing in a symbiotic relationship. However, they are a HUGE problem if they are existing in a free-living form.
LUCKILY FREE-LIVING DINOFLAGELLATES ARE RARE IN REEF AQUARIA
Dinoflagellates (hereafter called Snot Algae or Dino's) are one of the meanest things you have ever met in your life. (I unfortunately have had first hand experience). You will follow all of the advice and the problem will keep getting worse and not better. On top of that, some Dino's are toxic (think red tide). If you have a poisonous type, any snail, conch, fish, worm, etc. that eats the bad Dino's will eventually die while you are doing everything people are telling you to do. Then your clean up crew (bristle worms, crabs, etc.) will arrive for clean up duty and will die as a result of absorbing the toxins in the animals they are trying to eradicate. This provides more nutrients for the Dino's to grow.
They have one interesting characteristic. You will follow everyones advice and go to bed. Then you will wake up in the morning thrilled that the advice worked. It looks pretty darn good---almost everything thing is gone. You go to work---come home 9 hours later and the snot algae is even bigger than yesterday.
If nothing is working, you might have Snot Algae. This algae is different. It is usually brown, has ton's of oxygen bubbles in it, dissapears to a great deal (or entirely) overnight. (Remember it is photosythenetic---that's how it helps your corals grow). I'm a guy and don't have any problems with talking about Snot and after a week or so of a Dino outbreak, you will know why it is called snot Algae. Same grossness---Same consistency.
HOW DID YOU GET IT AND WHAT DO YOU DO ABOUT IT?
First off, the mere presence of bubbles does not mean it is Dino's or snot algae----cyanobacteria can trap bubbles temporarily that are trying to exit the sandbed. As a result, some bubbles can be present with it too. Luckily, most of the time, it is cyanobacteria. Dino's are usually caused by two things.....Bleaching of corals due to extreme temperatures or a major swing in tank chemistry.
Even if you have non-toxic Dino's, they are still dangerous---precautions must be taken. They have the ability to take up a lot of oxygen. Your fish can "drown" due to the lack of dissoved oxygen not to mention the Ph impact.
Again, I want to remind you that this is rare. Usually it is cyanobacteria. However, if you follow a lot of advice and nothing improves, it might be snot algae.
Most of the treatments for cyanobacteria applies to Dino's. However, Dino's require a little more. The Ph must be bumped up substantially during the day (I went to 8.5) and the lighting must decrease substantially.
Here are a couple of links