[dobz55]

Me again,
I have just had the lights of in my tank only live rock at the mom,I actually saw something that lokced like a crab or something else crawling out of a hole in the rock it quickly darted back in so did not get a clear view,
I know it,s a dumb question should I be putting some food in the tank to feed this creature, (when i bought the rock i was told that i dont need to put food in untill i put the fish in )

dobz

[leebca]

Hi again!

I generally like to feed my live rock, but indirectly. If you are following what I recommend in the way of setting up a fish only tank (See: What is Live Rock, Anyway?) then after the live rock has been in the system for a short time, you should be introducing your clean-up crew. The feeding of the clean-up crew will also feed the hitchhikers on the live rock.

[dobz55]

Thank you ,

now next question for the clean up crew in my tank around 150litres/50 or so gallons what should i use,

Dobz

[leebca]

It depends upon what you like. Your tank is too small (IMHO) for a carnivore sea star or a cucumber. Shrimp do well, but only if you keep fish that won't eat them. Snails do the most and best work in my opinion. When you obtain snails make sure they come from tropical waters. If they come from cooler waters (Mexico and Florida) they may slowly cook to death in the hot tropical home aquarium. Tank bred snails are the ones to search for (and pay more for).

Here are more references for you to read:
Cleanup crew article on Reefland:
http://www.reefland.com/rho/0305/medprod3.php

3 articles on snails:
The Grazing Snails, Part I - Turbo, Trochus, Astraea, and Kin by Ronald L. Shimek, Ph.D. - Reefkeeping.com
The Grazing Snails, Part II - Abalones, Limpets and Nerites by Ronald L. Shimek, Ph.D. - Reefkeeping.com
The Grazing Snails, Part III: Conchs, Ceriths, Cowries, and Columbellids by Ronald L. Shimek, Ph.D. - Reefkeeping.com

Aquarium Frontiers Library

AVOID ALL HERMIT CRABS

[wozza]

hi, sorry to butt in, but why in a fish only tank should you avoid all hermit crabs?
i have six in my tank and they never cause any problems.
ive got 4 red leged 1 mini blue and one i dont know what kind he is!

cheers james

[leebca]

Hi James. By consensus experienced hobbyists, and knowledgeable sources agree on the following:

1. Hermit crabs are omnivores. They will eat whatever they can get their claws on. They will eat fish, snails, corals, other invertebrates as well as their 'clean up' duties of eating left over food, micro algae and even diatoms. Many reef fishes 'sleep' by lodging themselves into a crevice or hole in the live rock. Hermit have been known to attack and injure sleeping fishes. Some fish deaths have been attributed to a hermit crab attack.

2. They are aggressive. As they age they get pretty belligerent. If left underfed you can expect them to begin moving any rock they can, to get at food, as well as eating any other Marine life. As they age, they become quite aggressive. If they think a snail has a good looking shell, they'll kill it just for the shell.

3. They don't always eat what you want them to. Hermit crabs are also opportunists. That is, they will eat whatever is available and starting with what they want to eat. By the time they starve enough to get rid of some nuisance algae, they are in the mood to attack/consume other marine lifeforms -- the ones you bought to raise.

4. They are a high-profit margin item. A retailer may buy them for nickels a piece and sell them for dollars each. Because of this, the greed to get them into the hobbyist's aquarium is strong. Those who sell them want to make their money and will encourage everyone to put them into the tanks. Some are sold as 'herbivores' that will rid the tank of certain micro algae. Not.

If you check out some of the writings I referenced in the earlier post, they will address the downside to having these crabs. Hermits are interesting, but not suitable for a marine aquarium, whether fish only or reef. They are genuinely not worth the risks they pose. Their 'clean up function' are easily handled by snails and less aggressive marine life that can be chosen to get along in a reef or community fish tank.

I think their greatest value is as a natural food source for some triggers, puffers, lionfishes, wrasses, etc.

[dobz55]

Good morning all,
thank you for your advise it looks as though I had better go buy a snail or 2,also I think I would like a shrimp or such, amazing isn,t it most would think a 3ft x 18in x 18in would be plenty big , I also have a 6 ft tank that has my African cyclids in it guess they will soon have to go LOL, this small tank shall only have a damsil, a clown , and one or 2 similar types, will a shrimp do okay with these

Dobz

[leebca]

The shrimp should work out fine with that fish grouping.

[dobz55]

thanks leebca

[wozza]

hmmm....shame.
My six line wrass does exactly what you said some fish do, sleeps wedged in a rock crevice, so it looks like im gonna have to make a invert only tank as i quite like my little hermits and dont realy wanna get rid of them.
thanks for the advice

james

[jsheffel]

Originally Posted by leebca

Hi again!

I generally like to feed my live rock, but indirectly. If you are following what I recommend in the way of setting up a fish only tank (See: What is Live Rock, Anyway?) then after the live rock has been in the system for a short time, you should be introducing your clean-up crew. The feeding of the clean-up crew will also feed the hitchhikers on the live rock.

I looked at the links you provided and couldn't find anything describing what to feed to the clean-up crew (that will also indirectly feed the hitchhikers on the live rock). I put some live rock in my newish fish only tank about a week ago and don't want any of the cool things poping up all over it to die.

[leebca]

Sorry for the difficulty in finding the information you want. In Setting Up a FOWLR Aquarium I mention in item 13. to feed the crew whatever it is they like to eat. Since I wasn't sure exactly what the choice for cleanup crew would be, I couldn't list exactly what to feed them. However, in item 15. of that same post I do mention the clam.

For carnivorous snails, drop in a living clam that you've cleaned, opened (without using heat), frozen, then thawed. Just place it on the substrate. The snails and other worms will find it. Also, you can feed shrimp pellets that sink to the bottom. The other (rock) lifeforms will find it too.

For herbivorous snails. . .If the aquarium hasn't begun to show signs of algae growth, you can sink a piece of nori or seaweed sold for fishes.

Usually, the bits and juices missed by the larger lifeforms will feed some of the filter feeders on the rock. The worms associated or that came with the rock will find the meat and pellets.

For shrimp, they will like the living clam (see above). If they are cleaner shrimp and young, they will also relish a feeding of live baby brine. I spot feed them with a tube. The shrimp would hang onto the end of the tube and, as I slowly released the living b.s. would scarf them up. The b.s. that get away will feed other rock inhabitants. You can sink bits of fresh scallop flesh and krill and what gets away from the shrimp and snails and worms, will help feed the rock.

The possibilities are quite numerous. Just use seafoods as much as possible, although pellets now and then are a good choice.

[jsheffel]

Thanks. That's exactly what I was looking for!