couple of questions

How many snails and hermit crabs are recommended for a 90 gal tank?
What is the difference between a sump and a refuge?

The sump can be just a part of the filtration system, a vessel that holds a sock, skimmer etc… a refugium is generally a lower flow area, with macro algae and lighted with a more warm spectrum of lighting (5000k ish) then a display for coral. A lot of us combine the two by locating a small fuge within the sump. A 30g sump/fuge can have a nice little 11’’ x 14’’ or so fuge incorporated that can grow plenty of chaeto and pods.

for snails and hermits theres no set rule. some folks wont allow any crabs in the dt, but the little ones never seem to bother much in my tanks. Snails, if you have enough algae, maybe throw 20 in there, try a couple and see what eats your algae… and some blue leg hermits, a dozen or so if you like them, i think they’re great little scavengers.

I’m not sure if there is a recommended amount of clean up crew (CUC) for a tank. But check out Dr. Mac website for what they recommend for problem tank.

http://www.pacificeastaquaculture.com/CleanUp-Crews-Prodlist.html

A sump is just that, sump. A place to be able to put or hide other things such as heater beside inside the main tank.
A refugium is a place you can add macroalgae to help with nitrate or grow amphipod or copepod for food for the tank animals.

Thanks guys!!! That is what I thought was the difference between them. I was told today that I should have one snail and one hermit crab per gallon of water. I thought that was a bit much.

[quote=“nerak, post:4, topic:6365”]
Thanks guys!!! That is what I thought was the difference between them. I was told today that I should have one snail and one hermit crab per gallon of water. I thought that was a bit much.[/quote]

Yeah, thats the “rule of thumb” i’ve heard for 20 years now… a mature tank will develop its own sort of crew and add to those numbers. after awhile tons of tiny stars and snails can reproduce pretty quickly.

90 snails and 90 hermit crabs just seemed to be a lot. There are a lot of the little white stars in it now, a few sea stars, 6 hermits and snails, and a couple of bristle worms.

I also agree that most of the listed “Recommendations” for crews seem a bit overboard.

To me it all depends on how much needs to be cleaned up. For me and my 90 gallon it was about 3 different snails. (I went no hermits)

Cerith / Nerite / Nass snails

10x Cerith snails: seem to stick to the sand and lower rocky areas.

10x Nerite: they go everywhere but the sand. when you see them on the sand its usually because they’ve fallen off the rocks or glass…and 90% of the time they’re upside down. If not assisted, they die and become Nass snail food. Its annoying, but they do the BULK of the cleaning of the rocks/glass in my tank. They’re AWESOME lawmowers.

10x Nass snails: They keep the top of the sandbed moving around to prevent stationary algae buildup. They’re there mostly to cleanup leftover fish food as they dont eat algae.

Over time, some have died off and need to be replenished. My lightng was sub par initially, and wasn’t creating alot of algae and some of them died off. However, I just recently changed my lighting to two ReefBreeders value LED fixtures for 240 watts of Full Spectrum LED goodness. (Prior it was just had 66 watt strip that had 66 1watt LED lights from AquaticLife) Algae production has gone WAY up, so I’ll need to adjust the cleanup crew accordingly. I’ll probably bump up my crew to 20 of each and add as needed.

A lot of the members are saying no hermits. Is there a reason for no hermits or you just don’t like them? My kids really enjoy the hermits. The only snails I have in my tank are bumble bee snails (that is what the LFS had them listed as). They don’t go on the glass. I have mainly only seen them on my rock. As far as my lighting goes, I just put T5 on it a couple of days ago.

Good questions re: the hermits. I’ve researched that they can annoy corals…that part of it I think is less common or even less of an issue. For me it was just a maintenance decision. You have to keep larger shells for them to grow into, and you usually loose some of them due to in-fighting because hermitA has a larger shell than hermitB, and hermitB wants a new home. hehe…that sorta thing.

I’ve also found one of the biggest problems with hermits is that when food is scarce they move faster than snails have no problems decimating a snail population. I also believe they do this because they want a new shell, need a new shell, may need a new shell eventually, or just get bored.

That being said, they do make a nice addition to the clean up crew, and I do keep a few in my tank, but I do try to limit the number of them for the above mentioned reasons.