Freezing Dino's Out (An Anecdotal Story)

[Michael's Marine Park]

Hello everyone,

I wanted to share an experience I recently had in the hopes it may help others who know more about dinos and how to treat for them. THIS IS NOT A RECOMMENDATION TO TRY THIS.

I have a 25gal waterbox mini peninsula that's 3 months old and stocked with two clownfish and a variety of zoas, firework cloves, montiporas, favias, acan lords, duncans, and others.

I started my tank with live sand and live rock and cycled for two weeks before starting to add coral & fish. My tank has been very stable until 3 weeks ago when I decided to put a skimmer in my sump to help with algae. A week after installing that, dinoflagellates started to appear and overrun my sand bed.

For the 1st week of dealing with them, I tried a 48 hour blackout, removed the skimmer, and manually removed them, but they grew back.

I then went on a week long vacation and when I returned, I discovered that my ATO malfunctioned, which caused my water level to drop 40% and exposed my heater which was in the sump and fried. Because of this, my tank was at 73 degrees F, my corals were all closed and my clownfish looked very slow. An absolute nightmare to come back to. I added warm water back to the aquarium and now have two heaters going for redundancy. All of my corals and fish recovered and I noticed that my dinos are completely gone and have not come back. I am no longer running a skimmer as I believe that contributed to the start of this.

I would not recommend purposefully bringing your water temperatures down, but I wanted to share this story for those of you who are more knowledgeable on dinos and may use this to help others with removal strategies.

 

[Idoc]

Interesting...

 

[educatedreefer]

Maybe removing the skimmer significantly reduced nutrient export enough to allow bacteria population to compete or outcompete the dinos?
Some reefers have reported increasing tank temperatures to upwards of 35 Celsius or higher to reduce dinos although, from my understanding, they can withstand a variety of temperature swings (https://www.researchgate.net/publication/226003802_Temperature_tolerances_of_toxic_dinoflagellate_cysts_Application_to_the_treatment_of_ships'_ballast_water)
I used to run GFO and a Zeovit system in one of my old tanks, but after removing both, my constant battle with reoccurring dino outbreaks finally subsided although I continued using a skimmer.

 

[taricha]

Some dino types have a seasonal winter hibernation...

"3.1.1. Resting Cyst Formation as a Strategy for Withstanding Unfavorable Temperature and Nutrient Conditions
Dinoflagellate encystment is generally considered a response to the stress imposed by suboptimal growth conditions. Among all environmental factors, nutrient limitation and changes in temperature are the most common triggers for resting cyst formation"

Towards an Ecological Understanding of Dinoflagellate Cyst Functions

So it's quite possible that the temp drop triggered formation of cysts and a hibernation period for the dinos. These cysts can sometimes wait for months. Re-emergence from cysts may happen gradually, and perhaps only a portion of the encysted dinos will re-emerge any time soon.

just a possibility.