How big of a cleanup crew for a 20 gallon?

I used to have a bigger one, but since all my hermits killed each other, along with most of my snails, I think I need to restock.

I have about 5 nassarius snails, one blue leg hermit, and one star fish (3-4 inch diameter). I just feel like they aren't getting it done. Let me know your input.

 

The nassarius snails won't eat algae, they eat "dead stuff". The hermit won't do much and the starfish will die (sorry :-/ ); they don't do well in our tanks, especially a small, new, unestablished tanks as they eat live microfauna. You may want to look at some cleaner packages for your size tank. Reefcleaners has some good options. You may not even need a 20g package, as you already have some nassarius, but it will give you an idea. If you get a lot, they tend to starve off too as the algae disappears, so maybe even a 10g package, without the nassarius. You can always add more if needed.

 

Go to reefcleaners.com and look at their pre-made packages. John is pretty amazing

 

Well I've had my starfish for about 4 months now, and he seems to be fine. I Wouldn't be surprised if it dies but my tank has been up for about 18 months now. I feel like its established, but I just have an insane amount of hair algae these days. I even spent some money and added a decent protein skimmer not too long ago and it still didn't help.
So. Much. Algae.

 

i have 2 turbo snails and 4 blue leg hermits in my 125gal and its sqeaky clean

 

+1 John isn't just pretty amazing- he is THE MAN! I've bought from him twice and he always has excellent service, great critters, has the best prices around and can build a CUC specifically for your tank.

AKA- just go talk to John.

In addition to the CUC, you just need to try to limit the nutrients in your tank. The easiest way to do that is with water changes. I used to have an issue with GHA and I found that when I pulled it all out by hand, then kept up my water changes, it disappeared.

 

The size of your CUC is a tricky thing IMO.I have never used a large one .IME the size needed is constantly evolving.You add a large crew they eat all the consumable algaes then slowly starve to death.Then the algaes come back and you start over.I like to keep my crew small and let WC's and chemical filtration do the job so I don't follow that vicious cycle of death. I have 6 Emeralds,4 Nassarius snails,2 limpets(came on my LR),and 6 Florida Ceriths in my 90 and it is plenty.I had a Turbo in my tank for over a year and it eventually starved(they are super efficient so I never suggest more then one and only for large systems).There are very few members of the CUC that will consume HA and the ones that do usually starve when it is gone.Manual removal and aggressive nutrient reduction is the best way to erradicate it.Also Bryopsis is very similar to HA and requires a different form of attack so a picture of the algae will help.Good luck.