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Sk8r
07/20/2007, 11:21 AM
This causes more grief than most other topics combined---and people WANT their fishes to be safe and healthy.

So let's discuss and ask, and maybe dispose of some misconceptions.

Number one myth: fish size themselves to fit their tanks. BUSTED: these are marine fish from a very big ocean. Many [tangs, angels] have juvvie phases and become very different fish as they age. Some [clowns] start easy-going as juvvies and change sexes on you, and become very aggressive.
And above all, they grow. If they can't grow any more, they just fade and die, because the tank can't support their growing need for oxygen and exercise---like trying to raise a great Dane in a puppy crate---the dog will grow, and become unhealthy, and so will your fish.

Number two myth: I'm going to get a bigger tank when he grows: it's not just the tank, it's your skimmer, your sump and your lights: it's very expensive to make that committment, and are you going to realize when it's time to do, and will you have the money? This can be a major problem.

Number three myth: one inch of fish per gallon. No. Fish come in all sorts of different body shapes. The gallonage requirement for a cigar-shaped 2" long dartfish is different than that of a 2" long puffer with a round body, or a stout little angelfish. Mass matters. And oxygenation matters. Quiet little anthias, peaceful things, right? But to be healthy, most of that species require as much as 6 feet of running room and a good turnaround to get what they need: again, like keeping a greyhound, you just have to figure they need to run. Tangs are another runner: they suck in oxygen like a ramjet, and go in tremendous bursts of speed. Plus they get 10" long, easily, and Vlamingis twice that. No kidding. This is not a fish for little tanks.
Then there's territory: a maroon clown female will claim about 50 gallons of space before it isn't worth her while to chase your other fish further---meaning that one clownfish will claim a huge territory for a tank. [Percs only want about 10" of your tank bottom.] And fish like mandarins haven't a clue whose territory they're in: they go anywhere, oblivious, so they're often getting nipped.

I offer these items as what I hope is a helpful gauge. Knowing your fish's adult size is a real good start, and if they're fast movers---or aggressive---they may try to claim more tank than you've got.

Keeping a fish-only tank with larger fish isn't for the faint-hearted. You have to know your fish very well, to figure who's safe and who's not. Ask---please ask---before you find one fat, happy fish in your tank and $300 worth of others missing. That's a bummer. And I did that once. It was a beautiful fish. But I took it back to the fish store and warned them what they were getting.

So don't think you're the only ones---I looked at that mouth [in the days before the internet] and it LOOKED like all my fish were too big for it. Ha!

You have the advantage of the internet, and you can be a little smarter than I was, so ask!

papagimp
07/20/2007, 11:27 AM
So sk8r, if you were to talk with a newb and recommend amount of fish, given all these variables, what would you recommend as a "general rule of thumb"? I've always played it by ear so to speak, I add fish until I feel the tank is stocked sufficiently. But I'm also used to freshwater tanks where I'd cram loads of tetras into them. Maybe some examples vs. tanks sizes?

Shooter7
07/20/2007, 11:32 AM
Some info from the reef fish forum here:

http://www.reefcentral.com/forums/showthread.php?s=&threadid=739380

Sk8r
07/20/2007, 11:39 AM
My own rule of thumb, which is hard to describe---but I'll try---is there should be some moments and places where the fish can feel 'alone', ideally with no other fish in sight; and where its biggest panic rushes play out before they hit glass. IE, it can calm down before it goes smack! or flip! out of the tank. You can help with well-designed rockwork, dividing up the space so that a fish can feel 'his' territory has limits. How to do?
I'd advise against copying a 'look', which may have been photoshopped [densifying the number of fish in the photo] or, above all, not going for the Nemo look: I'm not sure whether it's subtle humor that the Nemo tank is a disaster---I fear they just wanted more characters. Wipe all that out, and just start with the fish you really, really want---that has an adult size ok for your tank.
Then make him a territory, put him in your tank and see how HE likes it. If he's really aggressive---you may want to put him in your tank mentally, but start putting in the milder guys, leaving the room in the design that you know he'll need. Make mental niches, plan where you hope Somebody will live, and when all your 'rooms' are filled, but the big one, put the big guy in: as last-come, he'll mind his manners, hopefully. But hopefully you'll have gotten on the internet and read a lot about your cast of characters, so you know how this is going to work. Surprises with aggressives aren't always fun in this hobby, so have an idea where you're going.

This is kind of my way of going about a tank. Now, you notice I have all little guys in my list: this is the way I like it. But I've kept aggressive tanks, and moderate tanks, and nearly fish-onlies, and this set of 'rules' is more like 'guidelines.' ;) I hope they'll be taken as such.

And thanks for the link, Shooter: there's a lot of good info and discussion there---as you can see, there is still discussion on this topic past newbie-dom.

papagimp
07/20/2007, 11:44 AM
I prefer the smaller more peaceful community type fishies myself, and that is exactly where my problems comes into play, seems harder to determine what's too many with smaller fish, at least I find it so.

I'd also like to add, that in my experience, the footprint of the tank makes a difference with stocking as well. As you mentioned, an anthias may require up to 6 feet of swimming room, while you can have a 6ft tank of "xx" amount of gallons, but have another tank of similar volume with half the footprint. Makes for less surface area, less oxygen exchange going on, less swimming room, even though gallons are still there. This is why I tend to avoid the fish per gallon rules.

Rue
07/20/2007, 11:47 AM
I have to defend the 'rule of thumb'...

The 1" of fish per gallon of water is a freshwater rule...

I'd have to double check...but I believe it is 1" of fish per 2 gallons of water for saltwater...so they did take that into consideration.

And of course it's only a very rough guideline given to new fishkeepers who don't have a clue of where to start...it's to help prevent them from overstocking their tank...and as such it's useful. The amount of info. you need to get a tank started is overwhelming for many newcomers. If you try and explain all the ifs, ors and buts to the rule, peoples' eyes glaze over because they can't take all the info. in at once. But they CAN remember 1" of fish per gallon of water.

However, somewhere along the line, this rough 'rule of thumb' has become a 'rule' - and that's where the confusion arises.

It is not a rule!

Sk8r
07/20/2007, 11:51 AM
I worry about my little fishes getting excessive in my 54g corner wedge: I want everybody to have a 'spot.' More like building a neighborhood: you want enough 'houses' for everybody, and nobody being shoved out in their skivvies in the street. Gobies and blennies in particular want to have a 'den', and dartfish want one for the night, and I like to have particularly holey rock for that reason. Fortunately most everybody is peaceful, and some of the gobies will hole up together even across species lines.

Which is an example of the kind of things it's good to research: I'm not adding another long skinny blenny because blennies are notorious for not liking other blennies with the same shape. If I hear that a particular type gets along with the tailspots, I'd consider it, but not until somebody has accidentally done it and warrants it a safe combination. None of my fish has nipped fins and I like to keep it that way. Have I ever made a mistake? Bigtime. That's why all of us write letters in the newbie forum trying to say what works.

WinnipegDragon
07/20/2007, 12:27 PM
Just for comparison, my Red Sea Max manual said .4" of fish per gallon for Reef or FOWLR.

Now, here is another question. Is that for the display tank only (i.e. swimming space based) or does that include sump/fuge volume (water quality based)?

Shooter7
07/20/2007, 12:27 PM
You could have a 10g tank with a 100g sump.

Sk8r
07/20/2007, 01:28 PM
It's got to be swimming space. Remember Disney's Aladdin? "Whole lot of power...ITTY BITTY LIVING SPACE." Sure, the bigger the sump/tank combo the more stable. But you need room for the fish to stretch out and feel comfortable.

Now figure---most little fishes don't move much: in their whole lives, their 'cliff' may be a rock you or I could lift. Their house may be a shell at the base of that cliff, and for them, our tanks are a pretty good deal, long life, no getting scarfed down as porpoise bouillabase, gulp and gone. We can offer them years of tranquility and a square a day.

The bigger fishes may patrol quite a bit of territory, but right along with that is how far can they go without bumping into somebody to challenge them: how plentiful is food and oxygen.

And what kind of fish are they? A big grouper in the ocean hangs close to a particular point, and eats anything that swims near it. Other fish are always on the prowl, yet may return to a territory as the sun goes down. And still others do the reverse: up and hunting by night.

The more we know about our fishes in the wild the better we can provide for them. One of the good tests is whether they'll breed in the space we provide---not a great test: some would probably breed no matter what---but a fish that will settle down and hang up a 'home sweet home' sign with a mate and try to raise young is doing pretty well. I had some clarkiis that got so good at this I had to sell them to a breeder/lfs person---you may have some of their offspring, many generations down.

Don't just imagine your tank: imagine the ocean, and try to make a good little slice of it for your fishes.

And some fish DO get the notion WE're the food source, at least. I had a silly betta that used to jump out of the water like an orca, take brine shrimp off the end of a toothpick and finish in a plunge to the bottom, mouth full. For my roommate at the time, that betta wouldn't even surface to breathe. I've had a baikur and koi that would take tubifex cubes from my fingers, and you could just see that these fishes were pretty darned happy getting that bonanza. They didn't spend their time in that corner, however, and went on at other times and had a lively time probing corners and politicking with other fish, which to me is a good barometer of mental health.

Yep, mental health. Zoos discovered that there's nothing healthy about bar-pacing behavior. Perimeter-pacing, they call it, and an animal that does that is in trouble. Ditto fish. If they hunt, probe, nibble, and have a 'patrol' that takes them in and out a varied course among the rocks, that's far healthier than a fish that's up and down, up and down for hours. Remember 'Bubbles," from Nemo? That's a problem. Keep your fish focused on being fish, not wearing their noses off against the glass.

kysard1
07/20/2007, 04:45 PM
You can intellectualize the issue till the cows come home but it doesn't really help people.

We need a pragmatic approach.

What we need is actual data from people who have long term success.

Start a database:

fish list and apprx sizes
# of years fish together
Dimension of tank
# of deaths and causes if known
Quarantine procedure

Enough people posts their data and we will start to see trends and people can see what an ideal fish list for their tank would be.
There are too many what-ifs and data absent theories floating around. I would love to see some data.

Toglco
07/20/2007, 05:42 PM
I like the point you make, Sk8r. We can more safely assume that our fish are doing well when they're acting like fish, not inmates.

Rcpilet
07/20/2007, 06:35 PM
<a href=showthread.php?s=&postid=10379644#post10379644 target=_blank>Originally posted</a> by WinnipegDragon
Just for comparison, my Red Sea Max manual said .4" of fish per gallon for Reef or FOWLR.

4" per gallon?

So, can I put a 200" shark in my 55?

How about a 120" barracuda in my 30?

A 40" eel in my 10?

Thats the biggest BS "rule" I've ever heard. I hope that book is out of production and hard to find.

Rue
07/20/2007, 06:44 PM
...er...not 4"....0.4"...

Rcpilet
07/20/2007, 08:48 PM
My bad. :o

Didn't catch the decimal on the front.

monicaswizzle
07/20/2007, 11:12 PM
Well, it is interesting to me that this discussion always seems "vauger"/more difficult for SW than FW tanks. I have kept lots of FW and realize the "rules" are hardly even really guidelines and that there is lots of debate as to which, if any are useful, but at least there people will say a "rule" or "guideline" in a format that makes it possible to see if you are under or over what the rule will say. I am not saying this is better, it probably isn't unless some of the guidelines are actually better than I think that they are. But, as a newbie to salt, it is interesting that I can't even tell if I am over or under by many people's definitions/guidelines/rules.

That said, I also have learned that although in FW most of my tanks are ridiculously understocked (by most people's approach), in SW I am constantly surprised by how much bioload such a small number of small fishes can give off. I have learned to be a lot more cautious in SW, and I am by habit cautious in FW. I do think that each person does need to get a feel for it themselves, although it is too bad that there isn't clear and reliable guidence for the really new. A lot also depends on what you are willing to put into tank maintainance (both $, equipment and time), so two tanks of the same size may have very different capacity due to "management".

Thanks for the discussion/ideas and letting me blab. One comment on Sk8r's approach about conceptualizing "rooms" and making sure every fish has one. Given that most of us, especially when new tend to "squeeze in just one more fish", you might want to plan to have several "empty" rooms that are used in common by all the residents.

Thanks again.

3n1
07/21/2007, 01:14 PM
<a href=showthread.php?s=&postid=10379356#post10379356 target=_blank>Originally posted</a> by Rue
I have to defend the 'rule of thumb'...

The 1" of fish per gallon of water is a freshwater rule...

I'd have to double check...but I believe it is 1" of fish per 2 gallons of water for saltwater...so they did take that into consideration.


I'd have to think this isnt a good idea for any beginner. As a newbie myself, I look for the smaller ( less expensive ) fish for my tank. I would rather have a pair of 1.5" Clarkii's for $30 than a pair of 3-4" Clarkii's for $50+. Or a 2" Yellow tang for $20 than a 5" YT for $70. Given that thought, if I could go with 1" per 2 gals, I could have 52.5" in my 110gal wide. Cool, 25 ( 2" ) Yellow Tangs would make a super neat school! Someone isnt stopping to think of the size of the fish full grown.

No, I think it is best to explain that there is no set "Limit" and it is best to get advice about each fish they want to keep and what tank they are putting it in. Not easy to remember, but surely better off than trying to crame 50" of fish in my tank.

Just my opinion, not that its the correct one.

Sk8r
07/21/2007, 02:55 PM
Fish grow amazingly fast when well-cared for. When allocating 'rooms', be sure you've allotted for the size that fish is in his head. ;) They kind of know how much space they'd like.

I have a little rainford that's only going to be 2" long as an adult. Right now he's just hit an inch, but he's hit it in two weeks, growing about 1/4 inch, if that gives you a picture. That's huge growth.

Remember that the world can be parsed mathematically, but even in our tiny slice of ocean, the variables are far more than just water/fish. One of the problems in trying to devise a formula is that the variables include such things as ratio of carnivores to herbivores, productivity of the tank in copepods, other microlife, what came in on your rocks, temperature, salinity, aptness of same for all fishes, which may have come in from shallows, in the Caribbean, in the Red Sea, in SE Asia, Australia, etc., your mineral chemistry, your oxygenation [dependent on skimmer, depth of your tank, type of lights, macroalgae, photoperiod, etc.], and your level of skill and dedication.
It's, to borrow a phrase, a "slice of life," and that's not even the whole list of significant variables, which is beyond most of us as biologists and mathematicians---
My conclusion: give yourself and your fish a bit of wiggle room. I've been at this some 40 years. I've had about every kind of fish but a trigger and a shark...but I had them sequentially, in different tanks, different circumstance, and certainly not all in the first year. Leave yourself, as Alexander put it, 'worlds to conquer,' and when you buy a fish, plan to have him for at least a decade---some have shorter lifespans, but many, many of these fish are capable of years in our care if we're careful.

The image occurs to me of one of those individuals who gets on the news for having a house with 30 dogs/cats etc, and a notable problem---sure there's space enough, given 3 bedrooms and the living room and kitchen. But boy are there issues!

Think about the 'house' you're putting together, and acquire your critters individually with discrimination, understanding of their needs, and years of life in mind. They're not acquisitions to wow your neighbors and they're not room decorations. They should be with you for a natural lifespan, imho which ranges from about two years for some of the tiniest gobies to a decade or more for some of the larger species. Don't even ask about groupers.

fatdaddy
07/21/2007, 04:06 PM
Hi Sk8r,

You make a good point as I have a 7" yellow tang in a 48" 110g tank that I can on describe as "barely adequate". I certainly agree that when stocking a tank, one should stay well clear of maximum limits for fish stocking.

And, I also agree that we need to maintain good habitats for our finned friends with a reasonable amount of swim throughs. For example, I built a nori game for my 7" tang where food is suspended by a rubber band to keep him from wolfing it down. Instead of nori lasting a few minutes with much floating in the surface skimmer, it lasts many hours of (hopefully) fish entertainment.

However, I am concerned about your myth about buying fish that fit your tank for the whole life span of the fish. There are certainly tank upgrades, and there is also the LFS which will buy back fish for resale into larger tanks.

I have juvies that will eventually outgrow their current enclosures. (I have a juvie grey angle in a 10g hospital tank which for anybody who has seen them in the wild, is wholly inadequte). However, I'm responsible enough to realize that they will need bigger and better as time moves forward. I've already purchased a tank that is more then 2x the size that I have currently own.

If I'm lucky enough to keep them healthy long term, I realize that they will need better surroundings and I may need to give them up to somebody with more resources.

However, under your guidelines, I'm clearly out of bounds of responsible stewardship of my aquariums.

Scuba_Steve
07/21/2007, 09:10 PM
<a href=showthread.php?s=&postid=10385727#post10385727 target=_blank>Originally posted</a> by 3n1
I'd have to think this isnt a good idea for any beginner. As a newbie myself, I look for the smaller ( less expensive ) fish for my tank. I would rather have a pair of 1.5" Clarkii's for $30 than a pair of 3-4" Clarkii's for $50+. Or a 2" Yellow tang for $20 than a 5" YT for $70. Given that thought, if I could go with 1" per 2 gals, I could have 52.5" in my 110gal wide. Cool, 25 ( 2" ) Yellow Tangs would make a super neat school! Someone isnt stopping to think of the size of the fish full grown.

No, I think it is best to explain that there is no set "Limit" and it is best to get advice about each fish they want to keep and what tank they are putting it in. Not easy to remember, but surely better off than trying to crame 50" of fish in my tank.

Just my opinion, not that its the correct one.

Just remember that any "rules" out there are using the fishes fully grown adult sizes, not the juvenile size.

3n1
07/21/2007, 09:33 PM
My point being many newbies have no idea what the Adult size of any given fish are. They are going to remember 1" per 2 gal however, and not make the right decisions.

Sk8r
07/21/2007, 11:54 PM
Not intending to bash any good, considerate fish owner: anyone who makes rubberband games for his fishes can't be far wrong---I think that's a great idea, and your fish are probably very healthy and happy, because they have something to do. The size problem is that upgrades, as stated in my first post, are sometimes hindered by circumstances and economics: pre-tty expensive. They do need to happen if you have fishes getting into the next size range.
And re 3n1, absolutely: good point and thank you for raising it: the LiveAquaria.com site gives the adult size on all fishes it sells...they also have a compatibility chart. DON"T believe them as implicitly when they say how much tank you can get away with: add 10% more, imho, and DO consider your other bioload. [a little note: I used to have a baikur about 2 inches above the max the San Francisco aquarium listed for his species: you can get individuals who are larger.] But they're really helpful. I use them a lot for info. They tell you a lot about the species and habits, adult size, and the compatibility chart [to the left] is great. Do give them a look, and I think they'll answer a lot of questions. Also just google the common or species name of your fish and you may drag in a lot of info off the web in general.

92cg60
07/22/2007, 01:36 AM
Good thread, unfortunately I dont have any useful info to help out. However.. last week I returned home from the island of Isla Mujeres in Mexico and managed to get in 8 dives while there.
I have a lightly stocked 150 gallon reef tank, and now feel sorry for every fish in there. My 2 cents.. ;)

virginiadiver69
07/22/2007, 07:31 AM
<a href=showthread.php?s=&postid=10388177#post10388177 target=_blank>Originally posted</a> by 3n1
My point being many newbies have no idea what the Adult size of any given fish are. They are going to remember 1" per 2 gal however, and not make the right decisions.

With the abundance of info literally at our fingertips, I can not think of any valid reason why anybody, newbie or not, could not find the max size of anything we put in our tanks. ;)

Thanks again for another thought provoking post sk8r. I must admit I am one of those who is planning an upgrade when my admittedly heavily stocked tank becomes wholly inadequate.

My method was to plan my stocking list from the start from least aggressive to most aggressive. I have done a good job sticking to it. I think it has helped me eliminate those impulse buys that could be way to easy. I wait at least 1 month between each new addition. I also QT for 4 to 6 weeks. So this give me at least 2 months between new additions to the display. As long as I'm running 0-5 Nitrates I feel comfortable that my stock is doing fine.
I do see a skimmer upgrade in the near future though. I will add the skimmer that will eventually go on my "upgrade".

3n1
07/22/2007, 07:48 AM
<a href=showthread.php?s=&postid=10389526#post10389526 target=_blank>Originally posted</a> by virginiadiver69
With the abundance of info literally at our fingertips, I can not think of any valid reason why anybody, newbie or not, could not find the max size of anything we put in our tanks. ;)


I bet if I polled this forum, 50% or more have bought a fish on impulse, right there in the store. I'll also bet that 50% or more here dont have internet access right there in the store available to them ( Blackberry, ect. ).

I just recently got a cell phone that will do the web, but it's too much of a pain to use in my opinion. I have now purchased a couple books to take with me when I know I'm going to the LFS. Problem is, I dont always know when I'm going to one.

( PocketExpert guide to Marine Invertebrates and PocketExpert guide to Marie Fishes )

Sk8r
07/22/2007, 07:53 AM
Just remember that any species of fish you see once is 'in the trade' and will be available again, online if not at your lfs.

When you start getting eyes like Mr. Toad of Toad Hollow and your heart starts going pitapat, just take a deep breath and have a second, merciful thought toward the fish you already own.

Ask yourself if it's fair to them to acquire a new roomie you don't know a thing about.

3n1
07/22/2007, 08:00 AM
This is very true, but I sometimes hard to do when your in my position. I live 1 hour from the "Nearest" LFS. Many, many times I have stopped at a LFS on impulse while being 3-5 hours away from home. Then, on top of that, the LFS has some great sale going on, like buy 1 get one free, ect. and it makes those impulse buys even harder to get away from. Hence the reason I bought the 2 PocketExpert guide books. But as mentioned, alot of times I have no idea I am going to stop at a LFS and dont have them with me. Impossible to have with meall the time unless I buy 3 copies of each book and keep them in my vehicles ( plus one more set at home to browse ).

Also wanted to add that even the LFS employee's havent a clue sometimes. FW fish are so mainstream that most LFS employee's know an Oscar, Tinfoil shark or Arrowanna(sp?) get huge, but SW isnt as mainstream.

<a href=showthread.php?s=&postid=10389585#post10389585 target=_blank>Originally posted</a> by Sk8r
Just remember that any species of fish you see once is 'in the trade' and will be available again, online if not at your lfs.

When you start getting eyes like Mr. Toad of Toad Hollow and your heart starts going pitapat, just take a deep breath and have a second, merciful thought toward the fish you already own.

Ask yourself if it's fair to them to acquire a new roomie you don't know a thing about. :D :D

Sk8r
07/22/2007, 08:10 AM
Good point: ask if your lfs has the book, or a book---mine will go under the counter and haul out their giant tome, and we go over habits and requirements on the spot---or if they're busy, they hand me the book and I look for myself. They may well have a good reference, because if anybody's going to run into new fish or hitchhikers they urgently need to look up, it's your friendly lfs owner---won't hurt to ask!

virginiadiver69
07/22/2007, 08:12 AM
<a href=showthread.php?s=&postid=10389569#post10389569 target=_blank>Originally posted</a> by 3n1
I bet if I polled this forum, 50% or more have bought a fish on impulse, right there in the store.


I think you are being polite. I would guess it is way higher than 50%. That is why this forum is infested with posts such as "HELP, my so and so is picking on my so and so" or "The jerk at the LFS sold me the wrong fish"
I personally think that planning a stock list before is the best way to greatly reduce if not eliminate the impulse buys. I also think that standing in front of the holding tank at the LFS is the wrong place to be making a decision.
You could keep your books with you in the car. My LFS happens to have the two you mentioned on their counter. They are excellent reference tools and have been my main resource. During the set up and cycle process I poured over my Pocket-Expert guide and made my list. Doing this has given me the opportunity to find nice specimens at a good cost in the juvi stage.

3n1
07/22/2007, 08:23 AM
then I would have to buy 4 sets. 1 for home, 1 for my Truck, one for my Car and 1 for my Motorcycle. I never know which vehicle I'm using for any given day. I drive them on impulse. Example, nice warm day and I got a few hours to spare ( not really, but I take them anyways ). I hop on the bike for a spin. Next thing I know, I'm a couple hours away from home. And what do you think catches my eye? A LFS with an appealing sign. Gotta stop there and check it out..LOL

But yes, I know what " I'M " supposed to do before buying, but I can't control the other guys ( and thats what this post has been about ).

virginiadiver69
07/22/2007, 09:26 AM
How 'bout instead of four books just one stock list. If the fish is not good enough to make it on "your" list it may not be good enough to be in "your" tank.
I hope Sk8r's thread does not go off topic but I think this all follows what I think is his underlying theme of planning your tank thoughtfully.