newbie how do i gauge the gallons of my tank????

30 x 12 x 16=5760 divided by 231 gives you 24-25 gallons i think

You need to subtract the depth of the substrate to that as well. With a 4" substrate, for example, my aquarium software program says it's 18.73 gallons, but doing the calculation manually:

30wx12dx16h = 30wx12dx14h (16"h-4" substrate=14")
So. . .
30 x 12 x14 = 5040
5040 x 0.00433 = 21.8232 gallons or 22 gallons

I think there's another factor thrown into the software calculation -- probably a percentage for displacment due to decorations et al. Or it's because it's a Euro program. Dunno

If we allow -- hrm, some sites say 10% and some say 20%, so how about 15%? -- 15% for displacement, then it's:

21.8232 x 15% = 18.54972

Ah, that's very close to the software program's calculation of 18.73, so he's using a percentage displacement.

So the Net Volume is your calculation of 24.9408 or 25 gallons
and the Actual Volume is 18.5 gallons or 19 gallons

IMHO it's important to use an actual volume and not a net calculation when dosing with medications et al.

Roan
PS
Someone correct me if my calculations are wrong

25 gallons, check out this site http://www.drhelm.com/aquarium/areajava.html .

stingray4540 said:

25 gallons, check out this site http://www.drhelm.com/aquarium/areajava.html .

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25 gallons is the NET volume, without substrate
19 gallons is the ACTUAL volume, calculated with 4" of substrate

Nice link, otherwise. I'm going to check it out

Roan

Roan Art said:

25 gallons is the NET volume, without substrate
19 gallons is the ACTUAL volume, calculated with 4" of substrate

Nice link, otherwise. I'm going to check it out

Roan

Click to expand...

your absolutely right on that. You have to calculate for howevermuch gravel and decorations you put in, as well as how full you keep it. If you keep it an inch low you are going to have a couple gallons less in there for example.

stingray4540 said:

your absolutely right on that. You have to calculate for howevermuch gravel and decorations you put in, as well as how full you keep it. If you keep it an inch low you are going to have a couple gallons less in there for example.

Click to expand...

Yep, and I didn't calculate for that. Probably cause I'm one of the few dorks that fills their aquariums pretty much to the tops

I really like that link you posted. Very handy with the lighting and stuff.

Thanks!
Roan

nik270268 said:

thanks guys..........another little question......have bought some male guppies....how long before i can introduce some black mollies........it has been suggested 14 days......these are the first fish in a new tank

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Is the tank cycled? I'm assuming you went fishless since the first post said it has been "established" for about 8 weeks with no fish? In that case I think you are supposed to add all the fish at once. Hopefully someone will correct me if I have that wrong!