Needing help with tank after recent reboot

[kartrsu]

I recently moved from an apartment to a house (right around start of covid) and I decided to restart my display tank from scratch. The tank was running for a little over a year. I bought new dry rock and moved my old rocks into another tank to use as a frag tank. Now I'm running into some issues in both tanks and had some questions for the broader community. Would love some help to see if I am doing things correctly.

Quick background:
My display tank is a IM Fusion 20. I am running two AI Prime 16HDs for LPS and softies. One light didn't give me the spread I wanted, so I got two. Plus, it'll incentivize an upgrade down the road. Lights are 5 / 30 days into acclimation from old AI Prime HD settings (BRS) to David Saxby, with intensities dialed back significantly. Par should range anywhere from 100-200 across the tank after acclimation.

Display tank parameters & pic
Salinity: 35 ppt (milwaukee)
Calcium: 420 (API test)
Alkalinity: 8.9 (salifert)
Magnesium: 1350-1400 (salifert)
Ammonia / Nitrite: 0
Nitrate: ~10 ppm (salifert)
Phosphate: 0.05 to 0.1 ppm (Hanna ULR)
Temp: 78-79F
Return: Sicce 1.5 (half flow) with spinstream nozzles
Fish: 2 clowns, firefish, and neon goby

Frag tank is 10 gallon with old AI prime (using Saxby now) with HOB filtration and small powerhead. It's using old live rock.

Frag tank parameters & pic
Salinity: 35 ppt (milwaukee)
Calcium: 420 (API test)
Alkalinity: 8.3 (salifert)
Magnesium: 1350-1400 (salifert)
Ammonia / Nitrite: 0
Nitrate: ~5 ppm (salifert)
Phosphate: 0.02 to 0.05 ppm (Hanna ULR)
Temp: 78-79F
Invert only

Question time!

1) My new rocks are getting this hard dark green algae over the rocks. Doesn't blow off rocks and needs to be scrapped. It's getting a bit intense but I see spots of coralline popping up all over the place. Is this normal and should I be concerned? I'm worried its green boring algae and will start destroying my corals. I'm hoping coralline will grow over it in time, but in my old display, that wasn't the case for over a year

2) I've been, battling dinos over the past 2 weeks in the display. My nutrients kept dropping with phosphate undetectable and nitrate near zero. I didn't think much of it until dinos started to appear. I've confirmed its ostreopsis (the worst!) under a microscope. I'm currently running the AUQA shield UV sterilizer in one of the overflows. Also why I adjusted my return flow by half. The UV is running at 9 watts per total tank volume of 15G. I'm using Brightwell's Neophos and Neonitro to boost nutrient levels. Nitrate has been holding at 10ppm after a few doses, but I need to dose phosphate everyday (though less now) . Corals don't look super happy, but are doing a bit better than before. I'm running 1tbsp of Rox 0.8 carbon, but wondering if I should go more and replace more frequently than weekly. I dosed MB7 for a while, but I read that it isn't effective against ostreopsis, so I'm hoping to use detritus from my frag tank to add biodiversity. No water changes or nutrient absorbing media. I occasionally vacuum the sand and recycle the water, but need to get 10 micron filters to strip out dinos. How does this approach sound so far?

3) GSP in frag tank is not doing well. Used to be fully extended but now it's quarter extended. Since it's an easy coral to keep, could this be an initial sign that something is way off? The parameters all check out, I added new carbon not too long go, so the closure is strange. I was running some crappy low par LEDs for a while, putting out 50-80 par at best, but now have the prime. However, I remember GSP doesn't need much light, so the poly retraction is kind of strange. Inverts are doing fine though.

4) Hammers and frogspawn in display have some receding tissue around the edges. I think the green hammer tissue has been moving up slowly over time but getting close to the bony ridges. I think there might even be some ridges that stick through on the bottom. My frogspawn is a wall type and I got it with thin tissue around the edges too. All of them have had no injuries to the best of my knowledge. I'm hoping the reduced flow helps, but does this recover? What can I do to create the best outcome.

look
5) Duncan poly extension looks funny, less puffy than normal. It's sprouting a bunch of new heads. Is this normal for it to look like this?

6) Last question! I previously ran AI prime settings at BRS recommended with 2 hr ramp up and down for 10 hours of lighting. With Saxby, its more like 13 hours. He ramps up his whites heavier near the afternoon. I notice my corals are plump to start then close up when whites ramp and then plump up and then close up again when whites ramp down. Peak par is around 90 near the surface, with 60-80 down below. I'm hoping the corals should adjust with time, unless this is actually a bad sign!

Thanks for all the help everyone! Hoping to do a build thread when I get a chance.

 

[Flippers4pups]

1. Completely normal. Could be start of coraline algae.

2. Keep your nutrients up as your doing. Typical for dinoflagellates to take hold when nutrients bottom out. Getting rid of them......I'm still battling them.

3. As long as the GSP tissue stays purple and rubbery, it will bounce back.

4,5 and 6. Reduce you light photoperiod to max 6-8 hours total for now. Even reduce the intensity by 10-20% till they look better. Watch for BJD.

 

[kartrsu]

Thanks for the feedback! I've noticed that my dinos have started to form less and less. I used some of the gunk water in my frag tank to seed the biodiversity a couple days ago, so perhaps its starting to take effect along with the nutrient dosing and UV filter.

GSPs still aren't opening up but are purple and rubbery. I'm going to do a near 100% water change and dose some nutrients to juice up the water to avoid dinos. Hopefully that'll freshen up the water.

Euphyllias are looking great and I hope it'll stay like that. I have my lights on acclimation mode, and perhaps they just needed an adjustment to the new settings. Par is barely a 100 at the surface so intensity is already pretty low. No BJD, thank god.

Starting to win the battle I hope. I'm getting green dust algae over the glass, and I read that's usually a sign that things are turning for the better with dinos. My green cyano hasn't been returning as intensely as before, so something is working, and the corals look great!

I ran a Hanna copper test for fun, and noticed detectable levels. It's strange, and I'm testing my tank and RODI via ICP to see if the test kit is just too sensitive at ultra low levels. Nonetheless, as safety, I refreshed the carbon and added in polyfilter to help take out anything that shouldn't be there.