Fish Count Advice

[Tarpan]

Hi all, I know this isn't an exact science but I would like some advice anyhow as the last thing I want to do is overload my tank.

My tank is somewhere between 37.5-40 gal.

I currently have this stock:

1x Male Beta Splendon
2x Sailfin Molly
5x Zebra Danio (leftover from my cycle)
1x Common Pleco

So far I just have fake plants but will look to start a switch to live plants in probably 3 or so months


I would like to add a couple Hi Fin Lyretail Swordfish and am also looking at other Molly's.

I'm not sure, beyond that, what else I could safely put in there. The advice that I have been given so far is that the Molly's will be fine, as will the sword tails. I'm told to avoid guppies due to the Beta. I would love to put angels in there, but have read that is a no-no with the Beta as well.

Any thoughts on what I can add into there as well as how much more load I can safely add would be greatly appreciated.

 

[rob158]

Is it a male beta you have?

 

[Tarpan]

Is it a male beta you have?

Yes, a male Beta. A fairly important point I missed. Sorry.

 

[Aqua Tom]

Is it a male beta you have?

Yes, a male Beta. A fairly important point I missed. Sorry.

The Beta may have a pop at the sailfins. You have plenty more room in that tank yet.

 

[Tarpan]

The Beta may have a pop at the sailfins. You have plenty more room in that tank yet.

Really eh, I will have to keep an eye on that. So far I have been worried about the opposite. The Sailfins are a fair bit larger and dramatically more active so the Beta has seemed quite intimidated so far.

 

[waterdrop]

You're right, it's not an exact science at all. It's both simple and fussy. You look around TFF, wikipedia and other sites (sites can vary quite a bit, so its helpful sometimes to look around a lot and get a feel for this - sometimes you find a breeding site for a single species and they'll possibly have the best adult size data of all.) From this you pick some number of inches to take as the eventual adult size of one of the fish. Assuming you were referring to US gallons, you simply look at that and say you'll allow roughly 40 inches (because it's 40 US gallons) of adult fish length (fins don't count) total bioload in the tank. Then you make another pass and consider whether any of the species are particularly large or small (hint: a common plec might need to count as more than it's number of length inchs because it's "mass" will get big, whereas you could have extra neon tetras because they have such small mass per length - you just use common sense guesstimates in this area. And of course, there are whole other "passes" you must make over your stocking plan to cover separate issues: minimum shoal size (on a per species basis), within species sex and numerical considerations, between-species aggression considerations, minimum tank length considerations for fast fish, minimum tank height considerations (for example, angels need at least 17" tall tanks.)

This of course follows the "rough inch stocking guideline" that we recommend for beginners. We recommend this because if you have a successful first two years of fishkeeping, it allows your baseline knowledge to "feel" right, after which you will better understand when things "feel" wrong with your tank. Even beyond your two-year beginner period, most experienced aquarists learn to think about stocking in many, many different ways: power outages are a big reason low stocking is safer. Understocked tanks often look more natural and are certainly easier to maintain. Overstocked tanks can, however, have that interesting "reef" look that I think many are going for... it's actually interesting to realize this is mostly a marine phenomenon and quite rare in nature freshwater settings. (thinking of "reef look" here as many -different- species together, as opposed to single-species shoaling sizes, which can be huge for freshwater fish.)

~~waterdrop~~

 

[Tarpan]

Thank you so much for the reply.

Guestimating on something like a Pleco can be hard. Is it fair to base estimates on a size that he would grow to in a few years rather than maximum?

My understanding is that they can get up to like 2 feet. I couldn't see keeping him in this tank (3 ft long) if he was getting upwards of 1.5 ft (if that).

Using that guestimate of his 'move out' would these seem like accurate guestimations? It's what I came up with with some digging around as you suggested...

2 = Beta Splendon
6 = 5x Zebra Danios
4 = 2x Sailfin Molly
18 = Pleco?

Using that system I am already up to 30 so not all that much room left.

It's a good thing I love Pleco's considering how much of the tank he's having dedicated to him!

 

[OldMan47]

A common pleco will grow too large for your tank even if it were in the tank by itself. It is time to start thinking about how and when to rehome it before it becomes so big that nobody wants it. An adult common pleco, sometimes called a sailfin pleco, can reach 2 feet long and my LFS has some as big around as my forearm. The rest of your fish are fine in a tank that size. A Betta splendens is not the aggressive monster that many Betta fanciers would have you believe. I find they are often victims if they are kept with active fish since they cannot swim very quickly to avoid truly aggressive or nippy fish. Once you resolve the issue of a very large fish in a small tank, the pleco, you probably have room to add a few more small fish of your choosing. Swordtails or mollies would like the kind of water you should have for the fish already in your tank. Please be aware that mollies pay no attention to color or fin shape. As far as they are concerned, they are all the same fish and the results of the inevitable breeding become unpredictable when you mix colors or fin shapes.

 

[Tarpan]

I am aware of the growth potential of the pleco and am fine with it (and look forward to it).

He is a baby at this point and years away from it. Once he starts leading up to being too big for this tank I intend to either upgrade my tank size or get a second larger tank going. I get that most people aren't prepared for the growth potential of the Pleco, but not to worry in this case. I love Bob (my pleco) and plan to have him as a permanent fixture around here.

Thanks for the info about the Molly's. The Sailfin's seem much larger, for their age, than other molly types I am surprised they will cross-breed. That said, I don't intend to do any breeding at this point anyway.

 

[OldMan47]

The mollies will not likely give you a choice on whether or not they breed. Unless you keep only males, you will have molly fry.

 

[Tarpan]

The mollies will not likely give you a choice on whether or not they breed. Unless you keep only males, you will have molly fry.

Right. I am only keeping males at this point.

 

[Tarpan]

1x Male Beta Splendon
2x Sailfin Molly
5x Zebra Danio (leftover from my cycle)
1x Common Pleco
2x Hawaii Platy
1x Swordtail

I know the Pleco will cause problems as he gets bigger but he'll have a new home ready by then.

Loving the mixture of bright colours and high energy fish. So far everyone seems to get a long very well.

 

[Harlequins]

You may well end up stunting the growth of your pleco if you continue to keep him in your tank and its unfair on the pleco.