Question regarding the Inch/Gallons Rule?

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Ok I know this "rule" isn't completely accurate but i'm just trying to figure out how i'm doing with regards to stocking.

Tank in question 24G JBJ Nano Cube
About 15kg Kenyan/Malaysian LR.

Fish: 1 Midas Blenny (7cm) 2x false perc clowns (3cm)

So i'm sitting on approximately 13cm or 5.1" of fish. Is this fully stocked?
 

trad

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basically yes if you follow the inch/cm rule. alot of guys dont.

But you have a nano so recommend very low stock level. Do you have a sump cause you can count that surface area as well.

NB must look at the full grown legth of your fish i.e. the pruculars will get to 5cm and the blenny will probably add 2-3cm as well.

24G = ? L 3.8each? so about 90L, I would definately add some:

Hermits/Crabs
Shrimps
maybe a starfish

all the above kind of cheat the cm rule cause they're not fish.
 

jacquesb

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Hey guys - many people don't follow this rule, because of the following possible reasons:
- they have a LOT of smaller inactive fish (that don't need a LOT of swimming space)
- they have HUGE skimmers somewhere that can pull out a LOT of gunk (over-feeding as well as the waste the fish produce)
- with a sump, it makes it easier to have nutrient exporting methods, ie, DSB, algae scrubber (mostly also works as the refugium)
- some people over-stock in fish, BUT also overdo water maintenance - ie. every weekend changing 50% to 80% of their water...

etc. etc. etc...

So - EVERYTHING is relative - relative to how you would compensate for the over-stocking. So, no - it is a GUIDELINE, not a RULE. And if reefers actively decide to break that guideline, they know how to compensate for it.

The only thing with over-stocking UNKNOWINGLY - then the reefer/s MOST likely end up with deaths, and / or total system crashes.... (knock-on effect)...
 
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Will do. So what is the actual rule, how many inches of fish per how many gallons of water?
 

trad

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i see you do have hermits

dude if i can remember my method worked on surface area ??? so LxB EG. 120cm*45cm = Divide that by 110 and you get the cm of fish you're allow, i cant remember exactly but i did actuall read this in a published marine book, but like jacques said sooooooo many other factors to consider
 
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So for a tank of 24G (probably a big less because of the 15kg LR), with weekly water changes of appx 10% how many inches of fish am I looking at as a guideline?
 

jacquesb

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An example: IF, you would have 5 fish each of 5cm, then you would be PUSHING the limit. That means 25cm (10 inches of fish) in 24 gallons of water, minus the live rock - say 18 gallons of water....

In your case - you have 5.1 inches of fish in 18 gallons of water. So, I would say, +- a maximum of another 10 inches (25cm) of fish MAXIMUM. If you would add that skimmer you are looking at, then you would be in the safe zone again. I say MAXIMUM, because you MUST take into account that so many more fish will require MORE feeding, and the more feeding = the more fish waste = the higher the DOC's and POC's that needs to be broken down by the biological filter....

BUT, then again - this WHOLE game of keeping reefs and marine fish, is: "try and see what works for you"....

We can assist with guidelines, but what works for one, does not work for the other, and the other way around.
 
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As I have said Matt - the GUIDELINE is 1 inch of fish per 1 gallon of water...
Kewl! So I can put an 18" tang in my 24G nano. Nice :p (never)

The inch per gallon rule must be applied with common sense. You will have to research each fish you wish to put in the tank and look at its feeding and swimming requirements. Put 1 purple dottyback in your nano, and I can almost guarentee you, that you won't be able to put any other fish in there. In my experience most of the dottybacks are quite aggressive. Taking this into account, study, read, study, read some more and the understock or overfilter to be safe.
 

jacquesb

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Yeah - CyberVic. You are 100% correct. Therefore my first comment about putting fish in that don't require swimming space (that stay within a very small area).... AND, as you say - putting non aggressive species in - due to territoriality.
 
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Yeah - CyberVic. You are 100% correct. Therefore my first comment about putting fish in that don't require swimming space (that stay within a very small area).... AND, as you say - putting non aggressive species in - due to territoriality.

Hehe, sorry I just had too. Some people will read your post, my post and 100 more like that and still overstock :p
 
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SIMS: trying to enjoy my nano, then when I qualify from studies i'll buy a 17000L tank for the waiting room in my practice ;)
 

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Guys the rule/guideline is 1inch of fish to 4 gals, not one gal, as above, there are many factors, and ways round it, BUT unless you have one hell of a skimmer, to pull out the crap, and a huge system, don't push it, Matt you have 24gals, there is no room for error, the system i am building will be around 200gals, but i still wont be pushing that guideline, what you want and what you should do, are rather different.

Justy get a bigger tank:thumbup:
 

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