Weekly discussion - Reef Janitors - help or hype?

[Anonymous]

i agree with those tending to sway towards "hype".
when i used snails and hermits to control an algae outbreak the end result was tons of detritus in every concievable crevice of the tank. no algae for awhile but then a huge water quality problem would start another algae bloom. my belief is that people end up with bryopsis because snails and hermits don't wanna eat it.

the addition and fatality of the snails and hermits also create swings in the bioload that i prefer to do without.

i have a couple snails and a couple hermits left from the time that i thought they were necessary, but i don't plan on buying any more.
snails tend to proliferate on thier own (these are small 1/8"-3/8" ones that reproduce in my tank) if there are no predators to wipe them out. i think we have all seen what hermits tend to do to small snails.
bristle worms, 'pods are other self sustaining janitors, they will eat algae off a sand bed.
i also have abalone, and sometimes there are what appear to be cowries with tentacles that quickly cruise the glass. the cowries never last long, but always seem to reappear one day.
well , i am babbling now.....

 

[brandon4291]

A concept I may need to refine is my thoughts on reduction of detritus from crabs and snails. My thoughts are, waste particles that accumulate in the rock crevices and around the rock bases are composed of bits of food, fecal matter, slimes/mucous and plant matter. At this stage of decomposition, there are still nutrient values to the detritus--enough to put nutrients back into solution where algae gets a foothold.

Each animal that feeds and further reduces this detritus extracts its nutrient needs from this waste, so it should follow that the detrital feeder's fecal matter should be less rich in these algae-feeding compounds. In other words, detritus gets further reduced and less nutritious for each animal in the food chain that utilizes it. If the truth exists otherwise, clue me in!

 

[Anonymous]

Like all the other miracle fixes, I think it is mostly hype; add these magic critters to your tank and you will have no more problems.

Pasta worms (I can spell spegetti), bristles, brittles and pods are neat, but you also never add them in disgusting quantities, so I have less of a problem with them. It is the 1 per gallon thing I think is terrible.

I think it would be better to buy 10 snails because you like them, and let them breed up. Hermit crabs, don't really like em, and would not want 150 of them in my 150.

Currently I have bunches of stomatella, some astras and sandbed critters.

 

[Anonymous]

Each animal that feeds and further reduces this detritus extracts its nutrient needs from this waste, so it should follow that the detrital feeder's fecal matter should be less rich in these algae-feeding compounds. In other words, detritus gets further reduced and less nutritious for each animal in the food chain that utilizes it. If the truth exists otherwise, clue me in!

I guess the question is how much do they really impact the detritus? I mean, if you are feeding the tank well, why would they eat crap instead of the yummy food?

 

[brandon4291]

My guess is a hermit will have more access to detritus than whole food because they are opportunistic feeders, and are usually in second place to fish, brittle stars and faster/more mobile organisms who weed out all the prime cuts available. Im still in debate over if they are actually necessary, but it seems they may play a role in the captive food chain. My systems do not have fish or stars, so the crabs/snails and pods get most of the prime chunks.

 

[AllenF]

They also add an increase variety to the biotype with minimal bioload.

Tullock concludes somewhere in his book that the more variety in a microhabitat, the better, the more likely to be balanced and it makes easier for mother nature to do what she likes best (even in the confines of a tank) which is: Find a health balance.

Of course this all assumes you are using inhabitats which are compatible or in his examples, are found together naturally in their normal habit.

 

[Anonymous]

They also add an increase variety to the biotype with minimal bioload.

Tullock concludes somewhere in his book that the more variety in a microhabitat, the better, the more likely to be balanced and it makes easier for mother nature to do what she likes best (even in the confines of a tank) which is: Find a health balance.

Of course this all assumes you are using inhabitats which are compatible or in his examples, are found together naturally in their normal habit.

it's my opinion that hermits decrease biodiversity in a captive system. since thier numbers have been declining in my tank i have noticed an increase in other life that would otherwise be eaten or destroyed by hermits.

 

[brandon4291]

one thing is for sure, I dont use them anymore as my primary cleanup crew anymore because it takes one about 5 seconds to walk across a pico reef and close up every coral in there. I think if they are to be used, they're better off in larger systems where this type of infaunal depletion you mention Pod might be minimized. I mainly didnt keep them because of the constant food stealing!

I do currently tolerate this action from two boxer crabs, lybia tesellata. These crabs are the most exquisitely colored crustaceans Ive seen, red and white like Eddie Van Halen's guitar. They carry two anemones in their claws, because they are smart enough to wield them like battleswords at intruding animals/ this amazes me. And, they are very small, but they still remove food from slow corals such as red lobos, euphyllias, caulastrea etc.

They scavenge just like the hermits too, and since adding them Ive had no light growth of diatoms anymore on SB.

 

[Mogo]

I have a dozen blue legs, 3 or 4 turbos, and a couple astreas. The hermits come out at night in herds and eat algae, detritus etc. as the snails slowly go about their business. I rather like the additional biodiversity. More than that, the hermits are entertaing to watch. My kids have names for some of them. Therefore, the hermits especially, have alot of value in my tank.

 

[Anonymous]

I think they are beneficial just not in the quantities most online vendors sell them in. Your typical reef clean up crew might do fine in an established tank but people buy them for a new tank with little algal/waste/detritus to actually consume. What happens is they end up starving, hermits chow down on snails etc.

I am starting to be of the opinion that hermits are more trouble than they are worth - a few is ok but the masses of them some people throw into a mid size tank is just asking for trouble. A nice variety of snails and maybe even a conch or two works almost as well.

Emerald crabs are hit and miss too, I have some that are very mellow, and some that are definite pests with the other animals.

I'd get a few astrella, cerith, nassarius and maybe some nerites(seem to be good algae/glass cleaners) and a fighting conch and just blow detritus from the rockwork with a powerhead or baster a few times a week.

 

[Mogo]

My lfs told me that I should have 1 hermit per gallon. That works out to 140 hermits. Not happening. I'll stick with my small herd.

 

[Marrowbone]

IMO, saying you need to buy anywhere near one (snail or hermit) janitor per gallon for a new tank is hype and just a waste. I prefer one or two hermits per hundred gallons, because in my experience they are just too rough on all the other species, but still I want one or two to look at and to do their little part. I also prefer to buy about a half a dozen of as many species of small snails as I can find. Each species, if not exposed to predators, has a chance to reproduce rapidly. I'm bound to wind up with a decent number of the kinds that do the best in my tank.

I think the very best janitors by far are pods and worms. If you don't put any fish in your tank for a while, there is an excellent opportunity for pods and other hitch-hikers to experience a huge population boom. The key is that these pods can reproduce quickly and automatically on demand (supply of food), so that if any catastrophe happens that wipes out most of them (or even food declines), they can quickly rebound later. I believe that the more species you have capable of rapid reproduction, the stronger your closed ecosystem is going to be. And, in general the smaller the animal, the faster it is going to be able to reproduce as needed.