View Full Version : How many ancistrus is sensible?

05-07-2014, 04:48 PM
How many ancistrus can I sensibly have in a 40 gallon tank? I have two already but a friend has babies and wants homes for some. I feed pleco wafers now and again and can supplement with some vegetation if needs be. I was thinking of maybe having a couple more?

05-07-2014, 04:54 PM
That depends on..
1. what else is in there
2. current nitrate levels
but most importantly, decor and the fact if you can rehome the babies. These fish are territorial if not breeding so you need territorial boundaries and enough shelters. Also especially the common Ancistrus cf. cirrhosus is inclined to breed like rabbits. With 4 fish the chances of having males and females becomes very high.

05-07-2014, 04:58 PM
Currently 4 mollies, 1 swordtail, 1 pearl gourami, 3 platys, 2 khuli loaches and 2 ancistrus. Décor - basic gravel, some plastic weed and a large rock, room to add more hidey holes though. Suspect my current ancistrus are a male and female as bristles on one and hardly any on the other, though the one I think is female is smaller and young still.

Off to look up the difference between the two species!

05-07-2014, 05:49 PM
If you were going to do this, I would suggest only 1 additional. If you were trying to breed and get fry you could do 3f and 1m.

05-08-2014, 05:15 AM
1 male would be worked to death with 3 females

Sounds like it's a relatively bare tank... I wouldn't add it.

05-08-2014, 11:45 AM
You don't mention driftwood, but that should definitely be in there, along with some sort of cave-like structures - I use bamboo tubes but there are plenty of options like PVC piping.

If you think you already have a male and female I wouldn't add another. You will have plenty of your own babies soon enough to try to get rid of.

05-08-2014, 05:29 PM
Thank you - I was thinking of adding a bit of wood in there anyway so you have helped me to decide on that! Thank you for the advice above thumbs2:

05-08-2014, 09:12 PM
You could do 4 ancistrus. I've done so, successfully, but my tank is heavily planted with 3 large pieces of driftwood and plenty of hidey holes. If you have sand, they'll also dig themselves a hole on the side of the driftwood, so be sure that the driftwood you have is sturdy and seated appropriately, otherwise your pleco might create a cave-in and trap itself.

They are territorial and will squabble once in a while, but not often. Their squabbling is also usually harmless and they'll break away and go off on their own. I actually think this is akin to pack behavior, in that they're determining a hierarchy in a struggle for dominance. Hierarchies are often created in schools of fish, and this same behavior can be found among many catfish. I've noticed it among my Striped Raphael Catfish, as well. Once the order of dominance is determined, they live peacefully with each other. I've only seen one squabbling with my plecos and one squabbling with my raph cats and they've been fine ever since.

Add plenty of driftwood with caves, add some additional caves if you want and plenty of plants, and you'll be perfectly fine.

05-09-2014, 05:52 AM
I'm not too sure about the pack thing. At least not on my species. Squabbles are too consistent for that and they display few other interactions

05-13-2014, 01:52 AM
I'm not too sure about the pack thing. At least not on my species. Squabbles are too consistent for that and they display few other interactions

Maybe you just have a lot of stalemates. ;P

05-15-2014, 02:38 AM
From personal experience, all that a large variety of plecos(including ancistrus)need to be kept in larger numbers is their regular requirements(driftwood, a few caves, good water conditions, good diet) along with as much territory as possible. Some plecos will go from cave to cave because they like multiple areas, so it is very important to have many available territories to avoid disputes. If you can accomplish this, they may eventually become more comfortable around each other and share territory & eat together as well(this isn't common, but it does happen).
A large amount of territory is especially important if there is a large size difference of your fish. Larger & more mature plecos handle stress and disputes MUCH better than smaller ones.
I recommend a good piece of driftwood for each pleco, and as many caves as possible. Avoid sharp parts of rocks as well. Plecos love areas that they are in a somewhat tight space(at least mine do) so take necessary precautions to avoid possible fin damage. This way, if one has damaged fins, you will for sure know it was another fish and that there is a problem.
Feed in different areas of the tank also, the last thing you want is them fighting over food.