Looking for direction

[mjohns27]

I recently moved my 120 gallon tank to a new house. I was having problems at the old house with what looked like dinos, diatoms, or some sort of brown hair algae. It definitely looked like dinos at one point or another, but eventually started to turn more like a brown hair algae. I looked at it under a microscope with another reefer and it looked like Dino Amphidinium, but it seems to have changed since then. I originally tried Vibrant, which seemed to make the problem worse. I then tried Dr. Tims Waste Away with a few days of blackout, which didn't seem to help much. I eventually let things be in hopes that moving the tank would help things.
I had a temporary tank set up at the new house for about 3 months while I slowly set up the main display and acclimated everything. I used new sand but saved the rock from the old tank. The fish and corals have been in the main display for about 3 months now. The tank is looking the same as it did before I moved. Lots of brown algae all over the rocks and sand. It does not particularly look like dinos - it is not stringy and seems to stay when the lights are out at night. It also covers the rocks and looks like some sort of brown hair algae. The tank gets covered in a fairly solid film of algae on the glass within about 2 days. I have 3 powerheads going and lots of flow in the tank.
My tank parameters as of today are: NO3 0-3ppm, PO4 0.012ppm, Alk 7.8, Salinity 1.025, waiting to order Calcium and Magnesium kits.
I am not running any media at the moment. I used to run GFO at the old house but am wondering if the low PO4 and Vibrant caused the dinos in the first place. I am wondering what direction I should go from here.
Questions:
- Do you think the low NO3 and PO4 readings are falsely low due to the algae growth? It seems like the glass gets covered very quickly for having such low nutrients in the tank. Am I better to start feeding heavier and decrease how often the skimmer runs to increase nutrients, or should I start running some GFO and go in the other direction?
- Would the rubbermaid stock tank that I am using as a sump have anything to do with this? I have seen others use them without issue.
- Would a UV make much of a difference?
- Should I try decreasing the intensity of the LEDs? I am running 2 Radion G3s.

Any input is welcome. Thanks for the help.

[Member No. 1]

A good UV that's properly rated for your tank and set up correctly will have a huge impact on Dino's. I would never run a tank without one. Don't cheap out, it will only cost you in the long run.
Look at AquaUV https://aquaultraviolet.com/aquariums-2/ And if you go with this company, don't get the one with the wiper. It's just a PITA and not worth the extra money.
Also, in the mean time, if your doing water changes in the hopes to reduce Dino's don't.
All evidence I've read, suggests that all your doing is replenishing the nutrents the Dino's feed on. Dosing hydrogen peroxide @ 1ml/10 gal will help reduce them.

[reefteaser]

+1 on the Aqua Ultraviolet UV. It’s made a substantial difference battling Dino’s for me in my 115 gal mixed reef. As a result though, my NO3 and PO4 has increased dramatically, presumably because it doesn’t get consumed like it used to. I’m getting those under control though with an algae scrubber and water changes. I use carbon in a reactor also, and my water has never been clearer.
The glass tube inside the UV got coated with a lot of “slime” at first. The UV seemed to be loosing it’s effect and I thought something was wrong. The buildup seemed to dramatically decrease its effectiveness, but two days after cleaning there was a big difference. Now, the buildup is slower, but I still clean it every two weeks. I’ll probably be able to do it monthly soon.
So, yes, the UV is definitely worth a try, and I agree with the last poster—get a good one, and carefully plan the install. It’ll come with directions for proper flow. Also, plumb it from your sump to the display. Don’t recirculate it out and back into the sump.