Importing problems from old tank

[Futureproof]

Tldr; should I move live rock with green algae into new tank and fight the battle there or should I douse the old tank in gasoline and set it on fire?

So, long version;
I have a 100l marine tank that I've been re-learning on after many years away from the hobby. I had a massive green algae outbreak, the long wavy strandy stuff. I started with adding more critters, then upgraded my skimmer. My no3 is high and I was working to bring that down with water changes. Then my daughter picked the seal away from the bottom of the tank and we started leaking. The tank from the bottom, me from my face except they were tears of joy because the wife could no longer stop me from getting the upgrade I had been hankering for.

So I now have a 300l tank that has been drilled for a sump and has most of the pipework but no sump. I'm on a strict budget of whatever I can sneak past the missus hence I'm making my own DIY sump and DIY live rock but obviously I have a load of corals and live rock in the little tank, which doesn't fit under the cabinet BTW or I'd have repaired that used it as a sump.

So the question is do I use my hairy green live rock and fix the problem in my new tank or do I say stuff it and turf the lot of it over my neighbours fence?

 

[ngoodermuth]

Is it hair algae or bryopsis? I had success using fluconazole to rid my tank of bryopsis, some people say it works for hair algae as well. It's obviously only a band-aid though, you'll have to work on your water quality issue to keep it away, but might help you get a leg-up if you want to try to salvage the rock.

https://www.reef2reef.com/threads/bryopsis-cure-my-battle-with-bryopsis-using-fluconazole.285096/

I would still scrub and try to remove as much as possible manually during the transfer before treatment, if you decide to go that route.

 

[Halal Hotdog]

What I would do is put it in a tote with saltwater and cook it for 3 months. I would use lanthanum chloride to get all the phosphates out of it. By leaving it in a dark container all the algae will die off. You will have to do water changes to remove the waste that builds up from the dying algae.