New to the hobby: A few questions about various rule-of-thumbs

[nomadman2003]

I've been reading everything I can get my hands on while trying to mentally build my first tank. Not even really thinking about stocking, just working on making sure I get the right parts or kit to make sure I have a solid habit.

There are many rules-of-thumb that I've come across. I personally do best by understanding why a rule of thumb exists so I can use common sense when applying it. If I list a couple with my thoughts could you chime in with corrections or exceptions, I'd appreciate it.

-----
1"/gallon - seems like a bioload rule mostly but might also be an oxygen (surface area) rule. I understand some pets (like cory catfsh) have higher bioloads and should modify this (0.5"/gal?). Is there a resource outside of asking on the forums to look up if a particular specie has a heavy bioload?

Also, correct me if I'm wrong, bioload is mostly ammonia so will more filtration (larger biofilter) allow bending of the 1"/gallon rule?
-----
10gph filter per 1g of tank size - my LFS had a pamphlet that said 3-5 but ppl seem to go way over that, up to 10gph*#gal, also that gph is the real rating, not the manufactures suggested tank size. I do understand that more filtration doesn't remove the need for weekly PWC and substrate cleanings.
-----
5 watts per gallon - this one I haven't read online, again from pamphlet at LFS. It was also suggested on larger tanks (30g+?) to split the heater in to two heaters at opposing sides. Is this all correct?
-----
Swim areas - Again at my LFS, fish are labeled as bottom, middle, top, seems to me that you'd need a pretty tall tank before those areas existed. Is this true? Is there a good rule for tank height and which levels exist? Smaller tanks (10g-20g) seem like they really should be all middle or top-middle/bottom. Does that seem fair?
-----
1.5lbs of gravel / gal (for 2-3" flooring) - This one isn't as big of a deal, just wondering if it's in the ballpark as I have no idea how much gravel/sand to buy. I'm sure an educated guess will get close enough.
-----
Any others I should be aware of?

I appreciate anyone who takes their time to contribute to helping me.

Robert

 

[jakedalab]

Hi ya Robert. The 1"/g is kind of a guideline really. And if you do choose to go about it be sure you go off of the fishes full grown size would be. That helps avoid being overstocked once they all grow to full size. And as far as your filtration goes personally I double it. Like my tank is a 55 gallon and the filtration u have is rated for 110 gallons. No such thing as to much filteration.

 

[nomadman2003]

Thanks for the tips. I'll make sure when I start stocking I read about the various fish and make sure they are compatible with the each other and the tank. I have seen a few places where they say max size is x" but requires a tank much > x gallons. This seems to be particularly true around semi-aggressive fish, likely because of territoriality.

 

[jakedalab]

But see there are exceptions to the rule. Lol there's always some kind of loop hole. Alot of ppl that keep more aggressive fish like the cichlids and such that day you should overstock to prevent some of the aggressive behavior.

 

[jlk]

Best advice is to do your research first, then ask questions here, & then do more research! An inch of fish per gallon is an antiquidated notion- each species of fish is different & has different needs for housing, food, temp, water conditions, size tank, compatability, etcetc. In respect to filtration, its always better to over filter rather than under filter & i recommend 10x the filtration in general (ie- 200gph filter for a 20gal tank) especially for fish with a high bioload. Over-filtration, however, does not mean you shoud overstock. For gravel/sand, 1.5pds per gal is ballpark. I would start with 1pd/gal & see how it appeals to you. With pool filter sand (pfs), i used a 50pd bag for a 55gal & it plenty to be 2-3inches deep. Hope this helps a bit & please ask if you have any questions!

 

[mfdrookie516]

The best rule of thumb I can suggest is to ignore any 'rule of thumb' you see... except mine

 

[Wingman-Goose]

IMO the 10x gph is very excessive! I have two tanks which are both slightly overstocked and run filtration and turning the entire tank over 2/3 x an hour!

Alot of filtration is good but 10x turn over an hour can also cause a strong current which will not suit all fish!

A good maintenance schedule is important and water tests will tell you if your filter is doing the job! Just make sure there is surface agitation in the tank!

Everyone does things differently!

 

[nomadman2003]

Best advice is to do your research first, then ask questions here, & then do more research! An inch of fish per gallon is an antiquidated notion- each species of fish is different & has different needs for housing, food, temp, water conditions, size tank, compatability, etcetc. In respect to filtration, its always better to over filter rather than under filter & i recommend 10x the filtration in general (ie- 200gph filter for a 20gal tank) especially for fish with a high bioload. Over-filtration, however, does not mean you shoud overstock. For gravel/sand, 1.5pds per gal is ballpark. I would start with 1pd/gal & see how it appeals to you. With pool filter sand (pfs), i used a 50pd bag for a 55gal & it plenty to be 2-3inches deep. Hope this helps a bit & please ask if you have any questions!

Thanks for the advice. I am slowly digesting all the info I've been reading over the past couple weeks.

 

[nomadman2003]

IMO the 10x gph is very excessive! I have two tanks which are both slightly overstocked and run filtration and turning the entire tank over 2/3 x an hour!

Alot of filtration is good but 10x turn over an hour can also cause a strong current which will not suit all fish!

A good maintenance schedule is important and water tests will tell you if your filter is doing the job! Just make sure there is surface agitation in the tank!

Everyone does things differently!

Just to clarify 2/3 x an hour means 2 to 3 time an hour, not literally 2/3 (like 30g tank w a 20gph filter), right? 2-3x an hour is more like the filter that comes in the kits my LFS sells.

Do other people run things this way? I was shying away from the kits mainly for this reason, but was scratching my head to why they sell them like this.

 

[Wingman-Goose]

Sorry, I mean 2 or 3! 3 obviously being preferable, for example a 40g tank with a 120 gph turnover!