How do you keep a small frag tank from turning into an algae infested swamp?

[Brett S]

So I have a 220G display tank with a 100G sump and a small 20G frag tank connected to the same system. A large portion of the sump is a lit refuguim with cheato and a few other macro algae’s in it.

I’ve only half heartedly been using the frag tank for frags, primarily because it tends to get overrun with algae, which will kill all the frags I put in there. A few times over the past few years I’ll gone in to tear it apart and clean out all the algae, but within a few weeks the algae comes back and within a couple of months it has taken over again.

I expanded my refugium and let the algae there get established before I cleaned out the frag tank the last time, thinking that maybe having more algae growing in the fuge would help keep the frag tank clear and I also put a few saltwater converted mollies in it in the hopes that they might eat the algae and help keep things under control, but it didn’t make a difference.

Since the frag tank is only 20G I have pretty limited options for putting fish in there in the hopes of letting them take care of it. I tried some snails at one point, but they seemed to struggle with the frag rack and often got flipped upside down and died.

Other than manually cleaning everything every couple of weeks is there anything else I can do to help keep this algae free? Or is regular manual cleaning the only option here?

 

[OutsideBrian]

I am a new reefer but I’ll try giving ideas.
How is the frag tank plumbed into the system? My thought direction is if the frag isn’t getting water from the sump that the nitrates might be higher in that tank than the Dt?
Could you put an algae blenny in with the mollies? Or run a separate exporting support on the frag tank?
Just brainstorming here....

 

[norfolkgarden]

1 trochus, or 3 ceriths.
No astrea (not self-righting)

A small turbo might be masochistic. ;-)

 

[Spdjnky]

Dam I could not have said that better wish there were more replies or answers and help because I have a very similar problem. I have this diy Frag tank set-up and algae is already around my frag plugs which I know is going to be a problem long term. Here are a few pics (not the greatest) but I am looking for help suggestions on any improvements of how to get the 2 tanks set up right with frag racks and or ideas on different ways to grow frags. As u can see I already have Zoa's in the bottom 30 gallon. For the top I would like to do Some SPS corals but need help on the light and flow for that one.
The lights over the 30 gal on the bottom are a T-5 4 light fixture that I have 2 ATI Blue Plus lights and 1 Coral Plus & 1 Purple Plus. The top fixture is a 2 light T-5 with a ATI blue Plus and a ATI coral Plus. I have not set a flow rate yet.
I am running a full sump with a skimmer and refugium.

 

[brandon429]

Large uv sterilizer w help on the frag tank issues

One that is grossly overrated for the volume, not one that is matched. Pond sterilizers on Amazon are 200 bucks and see the ratings feedback they’re great. We put one on a 30 gallon nano reef at nano.reef.com and blasted the dinos right out of his tank. I know above examples are algae, they work great just the same in preventing water xfer of algae into a system that has no algae competitors like coralline or fish