Sex ratio of Dicrossus filamentosus

[illumnae]

A shipment of wild D. filamentosus "Barcelos" came in over the weekend and by the time I got to the LFS, only 1 female was left. I was advised that a reverse trio was the way to go and so I happily left with 2 males and the sole female.

Now that they're in my tank, however, I'm feeling 3 is too little and am thus thinking of adding 2 more in. Would the lone female be overly stressed with 4 guys wooing her, or is it ok to have 4 males to 1 female?

I have access to import small quantities wild D. filamentosus from Hong Kong, but the exporter is unable to confirm the locality for me, and I'm not really keen on mixing the locality and getting 2 females from him.

Can anyone advise if I should get 2 more females for a 2 male 3 female group, or would 4 males 1 female or even 4 males and 3 females be recommended?

 

[illumnae]

Just to add, I'm not necessarily looking to breeding them as my ph is about 6.0 to 6.2 and I read that they need really low phs in the high 4s or low 5s to have viable eggs. As such, my query is just about keeping them happily in my tank and not numbers for optimal breeding conditions

 

[Gillie]

If you aren't looking to breed themyou could just keep a group of males, in my expeirience they tend to be quite aggressive when there were females in the mix. I had placed a small groug in a 55 gal so the could pair off themselves and I would find one or two dead every day. So finally I got fed up with it and bought ten males, added a couple Rams and a school of Cardinal tetras and everyone was happy. The Dicrossus males even formed a school and swam throughout the tank picking around for food and occasionally chasing the tetras.If I can find it I will post a pic of them schooling.

 

[illumnae]

oops I already got 1 female in the mix. so far the 2 males have not been attacking each other and they have been swimming in a group of 3. would it be safe to add more males or should i even out the mix abit?

 

[Gillie]

Like I said that was just my experience with them, it may have been just those fish. If you have a female and there is no aggression so far they may be fine, but I personally would trade the female for a male. I think that the females are just a little too plain for a display tank. It really comes down to your preferance. Just hang tight for a bit and see what the others have to say and hopefully apistomaster will chime in as well.

 

[Mike Wise]

illumnae, you were given poor information by your LFS. D. filamentosus behaves much like poligamous apisto species - like A. cacatuoides, for example. Males will protect a territory, and breed with any female in it. If you don't want to breed these fish, then do as Gillie suggests. You can always sell/trade an extra male with your female.

 

[illumnae]

hi thanks for the info Mike and Gillie. I went on an impulse buy and got another 2 males yesterday before I saw these. The bad news is that this particular batch of wild D. filamentosus was cleared out (mostly by me I think, LFS had mostly DOA fish when they arrived) so I can't trade in for a male (and in Singapore where I'm based, LFS don't often accept trades after you've paid).

Should I take the female out and put her into another tank and leave the 4 males in there, or add another couple of females in (from another locality, sadly) to form 4 pairs?

So far (48 hours), no fights or deaths have occurred.

 

[illumnae]

Update: 4 males and 1 female

So far, 3 males and the female are chiling together alot, but the remaining male likes to hang back and stay on his own. He has the blue irridiscent line (which is how i ided him as a male), but is showing some black on the ventrals (someone told me black ventrals = female, is that true?)

i'm trying to find others who bought the D. filamentosus "Barcelos" from this same batch so that I can work out a trade (after all, I think I have the only female from this batch, so it should be an attractive trade offer!) but chances are low as of the 50 fish ordered, 40+ were dead on arrival and i bought 5 of the remaining ones. Hopefully I can work out a trade of my female for a male.

Alternatively, I can ship in wild female D. filamentosus from Hong Kong but without locality information, so I'll end up with 1 pair from Barcelos, a few females from an unknown locality to form a harem (selling off the 3 other males). They'll breed/interact better this way I guess, but the downside is that my tank isn't as beautiful (males after all look alot nicer), and I won't get a "pure" strain anymore.

Dilemma dilemma =(

 

[Mud Pie Mama]

When you find out which male your current female prefers then set them up in a small tank to spawn. Once done; move the male back into the display tank. Keep the female to in w/the babies a little. Then, six months from now, you'll have all the males you need for your display tank; and some to share or sell.

Personally this is what I'd try to do. If you have a species with a collection name, it would be nice to help keep that species in the hobby. (Especially having suffered such a high rate of loss - 40 out of 50! I'd almost feel obligated to breed them to replace the loss.)

 

[illumnae]

I caught them fighting today before even breeding, so i've removed the 3 extra males and left the alpha male (ie prettiest) in with the female. guess i'll try and install a co2 set to get the ph low enough for them to breed. it's currently 6.1 using Gex brand soil (similar to ADA but without the horrible clouding issues), so hopefully with co2 the conditions will be ok for them to breed.

1 pair is ok for breeding and i won't need a harem right?

 

[Gillie]

I'm sure they would be fine. Just because they will harem spawn doesn't necessarily mean they have too. By the way you will most likely have to hatch them artificially, Filamentosus are known to be terrible parents. Also I may be wrong but think the eggs are light sensitive requiring as little light as possible for proper developement, Mike would probably be able to answer that one.

 

[Gillie]

I'm sure they would be fine. Just because they will harem spawn doesn't necessarily mean they have too. By the way you will most likely have to hatch them artificially, Filamentosus are known to be terrible parents. Also I may be wrong but think the eggs are light sensitive requiring as little light as possible for proper developement, Mike would probably be able to answer that one.

 

[goodtimz78]

just wanted to throw in my two cents worth about my checkerboards... when i purchased mine, they were also in a batch that were predominately male, something like 4 or 5 to one. fortunately i was one of the first one's there so i was able to get some females. i asked about stocking ratios and the owner said that in the wild they are caught in very large number, and are less territorial than other dwarfs. he said that anywhere up to a dozen fish would be fine in a 37 gallon. erring on the side of caution, i picked up 6 (3 pair) and have had no problems with aggression, or even an sign of the fishing becoming territorial. they almost seem more like they are shoaling at times in groups of 3-4. i have had the fish since april and have seen no behavior that would indicate aggression/territoriality. just my experience...

 

[Apistomaster]

2 cents more from a D. filamentosus lover.
Despite the fact that large numbers of subadults or late stage juveniles are commonly imported, they sex ratio is nearly always heavily skewed towards the males. 2 03 females out 10 unsexable juveniles is not a rare occurrence.
I often have better success if I get to select my fish from a group of sexable fish because many hobbyists buy the more colorful males first and the fewer number of hopeful breeders would be wise to buy as many females as they can whenever they can. Dicrossus spp are Patriarch/Matriarch where one male can easily tend to 2 or more females if there is enough room for each female to establish 12 X 12 inches subdivisions. In this respect they are very much like most Apistogramma sp.

When out of breeding season or mood, I have had no trouble with maintaining reverse trios or large groups skewed toward a greater number of males vs females but it is better and in the interest of reducing the stress on the females if they out number the males.

A fascinating Genus and I am pleased that more species have been identified, if not yet formally named. They can sure give a SA Dwarf Cichlid lover a run for their money. Most of the time, they seem pretty demanding of primo water quality and low conductivity and pH. The dissolved organics extracted from the forest that makes the water a complex organic soup despite the low inorganic content seems very important to the well being of these fish.