Fish stocking

Hi everyone.

I was just wondering, I have read on a few places that a rough guide for how many fish you can have is 1" per gallon, but in other places I have read that it is just as important to work out the surface area of the tank and you should make sure that you have so much surface area per fish ( can't remember the exact equation).

Which of these is most important? I know that the amount of filtration etc plays a big part in how many fish you can have but I am confused now whether you should measure the fish or just the surface area?

Which is the best way??

Well IMO the surface area (S.A.) measurement makes more sense as it's to do with the amount of oxygen exchange available AFAIK. You can read more about it here. Remember that this is ADULT fish because sometimes when you add a lot of juvenile fish you think "Ooh tank looks empty, I'll just chuck in a few more " but once they grow, the tank could end up overstocked.

And how HARD it is to avoid doing that too! I always want to buy more whenever I go to the lfs and see them all swimming about just waiting for a home

but the other way works aswell if you get too many bigger fish then it meant you need a bigger tank so their the excuse to get the next size up lol

i think alot of things factor in stocking

bio-load i think is important too many messy fish and the filter wont cope and that does need to be factored in some how

I dont think that there's on hard and fast rule for how many fish you should have. ts probably best to use a combination of them all, and then get a filter thats bigger than you need too just to make sure

i went on think fish just now and i currently have 107cm of fish using the surface area i am able to have 152.4 cm of fish buth think fish says 337cms of fish (nearly double) so dont use their valuation

if i go by 1" of fish then i can have 60" of fish (us gal) which is also about 152.4 cm of fish

My tank
50g(uk) 60g(us)
48x16x18

I dread to think what the stocking guides would make of my cichlid tank..

there are 39 fish in at the moment, all juvies and will grow to between 4" & 7" but overcrowding is the way to go to crowd out the aggression. They havent half got some good teeth on them

So so you mean that you are supposed to 'overstock' a cichlid tank, or is that just the way you do things?

kbekl wrote:

i went on think fish just now and i currently have 107cm of fish using the surface area i am able to have 152.4 cm of fish buth think fish says 337cms of fish (nearly double) so dont use their valuation

if i go by 1" of fish then i can have 60" of fish (us gal) which is also about 152.4 cm of fish

My tank
50g(uk) 60g(us)
48x16x18

I was just reading on another part of the forum that Thinkfish do that - I wonder why that is, as they seem to be quite a good site for other things. I wonder what rationale they use for their calculations?

Diana wrote:

So so you mean that you are supposed to 'overstock' a cichlid tank, or is that just the way you do things?

Yes, you crowd the tank to dispers the aggressive tendencies. It's similar to slow moving fish acting as dither fish. We had 2 mpanga fighting the other night. They were lip locked and another fish came sauntering along and they just break up instantly. (they do have a few bits of their dorsal fins missing)
Obviously we over filter to compensate by having the external turning the tank over at a rate of 1200L per hour & the juwel internal at 100L per hour. We've never had nitrAtes above 10 and all other levels are 0.
Close monitoring is the key when this much overstocked :face:

Thanks MC, that's really interesting, so what is the minimum number of fish you should keep together - obviously I know it depends on tank size etc, but for your size tank, what would you nener go below?

I feel all newbie'ish asking all this, but I think it's fascinating!

I think I have read that lowering the temperature in the tank reduces aggression of cichlids because it makes their metabolism slow down and so they get a bit sluggish - is that right?

Sorry, this is right off topic isnt it, so please move it mods if you need to

The more you read on here, the more you realise you know zilch!

driver wrote:

The more you read on here, the more you realise you know zilch!

no the more you learn lol

You're right guppy, don't know exactly about how it effects thier metabolism, but basically the higher the temp the more aggressive and active they can be. But this also encourages spawning.
We have had it very high for the last few days, because it helps to speed up the whitespot cycle.
(BTW, when treating meds and raising the temp the oxygen level in the water becomes very low. Therfore it is extremely important to get as much surface agitation as possible. Just thought i'd add that)

I think the minimum number of mbuna in a tank is totally dependent on how many different species of mbuna.
We were advised to have a minimum of about 25-30.
If you have 1 male to 2 or more females of any species they should be ok. But this also depends on the species. As some mbuna are only aggressive to thier own kind (con-specific aggression), and others the opposite. Most are only aggressive about territory so the amount of available caves is a factor.
Overstocking helps these rules somewhat. For example, you could put 50 males of the same species in a small tank without any caves, then they wouldnt have anything to be aggressive about. Any aggression from a dominant fish would be spread to 49 other fish.

As for stocking levels, I think there is only 1 rule that really counts.
Can your filtration cope?
If they were sardined that they couln't even swim, then that would obviously be toooo far.

I think the inch per gallon idea came about so people like Juwel could give a rough basis on how much filtration is needed, therefore sell tanks with certain size filters, knowing that peole would have X amount of fish and debris for the filter to cope with.

But this is very vague, after all, 50 1" neons floating around, bobbing up and down, don't produce half as much waste as 25 2" bristlenose catfish.

When our mbuna are fully grown, we will have around 200 to 250 inches of fish in a 60 gallon tank. They are extremely active fish producing a lot of waste. Also in the tank, one 4-5" and two 2.5" brislenose that are constantly pooing for britain.

Even as Juvie mbuna they are in total about 80 inches. With the EX1200 filter running along side the juwel internal, we have 0 readings and almost not existent nitrate. We do about 40-50% weekly w/c to freshen things up, but that almost seems over the top for the reading we have.