14 months. Upgrade from 18mnth old 6 x 2 x. 2
I'm not well read on dinoflagellates but people who know me will tell you that too much time on my hands leads me to experiment and cultivate, particularly algaes and I keep a couple of dozen species specimens alive in cell tanks
I've had to deal with dinos twice in two different tanks. .The first time was because I stupidly built bommies with a paver base, as shown by Mike Poletta. I didn't know that pavers (at least here) are full of silicate and I nearly had to reboot that tank but finally worked it out.
So first the conventional wisdom, then what actually worked for me, even though it goes against my preference for natural methods.
The literature suggests that dinos thrive on silicates, nutrients,(mainly nitrates) and light. Many people recommend starving them of light and I tried that but to no avail. I put a sample inside a black sealed bucket for two weeks with minimal benefit. So to my thinking, cutting light alone won't do it. I tried the same black bucket with fresh ASW - better but nothing dramatic. I stuffed around with various methods of reducing light, nutrient & silicates, both in the tank and in the bucket, - meanwhile it was taking over my tank.
In the end I tried a few products that are meant to reduce or kill algae generically and all I did was kill some decorative algae I had hidden up the back, testing it in low light.
The only thing that worked for me was this and please note that although the chemical was the key, I don't know which parts of the combination were effective so if you try this, I suggest doing it exactly as I did.
The chemical component is Chemiclean which is actually recommended for red slime algae (I've used it successfully for that too)
BUT - BUT - BUT you MUST use it exactly as per instructions on the packet, particularly aerating the tank directly via an air stone & turning the skimmer off. I've heard of a new product 'Chemiclean Blue' which is targeted at other algae but I don't even know if it's been released yet, I haven't seen it yet myself.
Here's how I did it according to my tank log at the time:
Step 1.
Turned all lights off for entire treatment time plus blocked one end of tank with cardboard as it got light coming through a window. Note I keep lots of different critters but not SPS. Not sure how they would go with no light*.
Added two bags of carbon to sump, one in skimmer area, one in return pump area. You'll see why one in return shortly. Catalytic activated carbon is preferable.
Manually removed as much of the dino as possible every day, using a gravel cleaner to catch as much as possible. Ran skimmer extremely wet, it was pulling six litres of fluid a day.
Daily 10% water changes, all done by sucking up dinos with a gravel cleaner as above. I moved more than 10% but the rest went back into the sump via a 200 micron filter sock. Once I had made a serious improvement, step 2.
Step 2.
Increase magnesium to over 1500ppm. My salifert kit can't read beyond 1500. I used Kent Tech M as that's what I had on hand after experimenting with it to kill hair algae. You'll get a slight rise in PH but so be it. Mine didn't get higher than 8.45.
Lights still off. Skimmer off. reduced feeding to a light feed for fish every 2nd day, no coral or anemone feeding. Add Chemiclean as per instructions and from this point those instructions are your guide.
IMPORTANT NOTE: Chemiclean strips dissolved oxygen levels, increasing CO2 percentage in the tank. The air stone (critical) puts dissolved oxygen back and drives CO2 out of the tank, as all air stones do.
When it was all over I did 50% water changes weekly for 3 weeks and I've never had a hint of it since. A real PITA method but usually nothing that works is easy. This method was something I devised by taking what I considered the best bits from all the competing advice. I avoid chemical treatments if I can, ie I use hyposalinity treatment for ich, But I have no doubt that Chemiclean was the key. You situation will be different from mine but at least it's a start.
Good Luck.
*I keep critters that do not like sparkling clean tanks, ie gonies and many zoas so I don't dabble with SPS. I will if my gonis ever die but I've had two of them for several years and wouldn't trust their survival elsewhere.but not yet.
