Sterile Fish Only tank?

Just wondering how SW tanks with little to no colonized bacteria like those tanks that only have clean decor in them are able to sustain fish, or similarly like the fish only tanks at a LFS. I imagine there is a wet dry sump or something like that but I would think fish stores would not want to maintain bio balls not to mention they probably run a UV that would kill any beneficials that pass through it. Just curios how its done. I guess the more i think about it and as i write this it seems fish stores must have some bio media in the back to keep ammonia and nitrites at 00.

 

Sumps, bio balls, live rock/ rubble in the sump but not in the display, running a skimmer, mechanical filtration, carbon, and other media for added filtration.

 

Alot of LFS's have special filtration. I have seen my LFS filtration and they have like a huge spool of filter pad and a spray bar that actually rotates and sprays the pad like a dishwasher on slow motion. Kinda cool

 

The LFS I go to runs copper in all their FO holding tanks, and don't keep fish in the coral tanks. That cuts down on most of the fish specific pathogens. Several of the larger tanks are all linked together via a sump as well, so really they have a total water volume of around 1200 gallons. There is live rock and skimmers in the sump.

They have a couple display reef tanks that run pretty standard, if high end, filtration composed of wet/dry, skimming, UV, and live rock. They don't sell from those tanks.

They also perform pretty large water changes bi-weekly, like 15-20%.

All that together keeps ammonia levels down - but fish don't mind it nearly as much as inverts do. And since there's very little bioload on their coral tanks with no fish a simple skimmer and some live rock in the sump pretty much takes care of those tanks.

 

cool thanks. do you think they add any supplements to the FO tanks? I'm also wondering how they keep stable params in there as fish come and go so often but i guess there is a large sump in the back with plenty of bio stuff.

 

Large water volume. They sometimes dose a bacterial supplement. Never seen them dose anything else, so I don't know if they do or not... really no reason to.