LCA Dinoflagellates- Have you beaten them?

[TheDon]

Hi guys,


I am currently about three months into my battle with LCA. Honestly, I know people say it is a long game with these, but I am really losing the will!


I’ve thrown everything at it barring silicate dosing: I went down the UV sandbed sweeper route, dosed nearly 2L of copepods, and added 25 to 30 ml of phytoplankton daily. Initially, I ran the UV every other day, then backed off to every 3 to 4 days whenever brown spots appeared. I started out using Brightwell MicroBacter7, then switched to dosing ARKA Special Blend daily.


Last month, I switched over to Tropic Marin Nitribiotic, dosing 3 ml every three days before dropping down to a weekly dose after a few weeks. Recently, I ran the UV sweeper for eight days straight, and by the end of it, my sandbed was totally clear. I kept up with the phytoplankton, stopped running the UV, and started checking samples under a microscope—I found a few things that looked like LCA/Dinos, but none of them were moving.


I currently have a green biofilm on the back wall, and with the lights on full white, there is a slight green tint in a few spots on the sand. Fast forward to yesterday, and very light brown spots started appearing again. I tested a sample yesterday and unfortunately, I still have LCA—only a very few per slide (about 3 or 4), but I still have to look hard to find them.

Any advice from people who have beaten these? Should I continue with the sandbed UV? I have a mother 1L of copepods on order, so will be adding them tomorrow.

Many thanks

 

[TheDon]

Just to add, I haven’t done a water change in near 3 months so just using all for reef to top up on Alk,Cal,Mag. My Po4 and No3 have never bottomed out - Currently Po4 0.21 (Hanna) No3 35/40 (salifert)

Lowest they have been is Po4 0.05 No4 10

Tank started from a previous year old tank, upgraded to a reefer 250 with live rock/Bio balls/ceramic block from previous tank and just used new Caribsea pink Fiji sand.