cave geometry

[DKcincy]

For cave spawning plecos, has anyone studied which geometrical measurements are ultimately the most important in successful cave spawns?

is it the size of the opening? the depth of the tunnel? is it critical for the tunnel diameter to remain constant? if the opening starts out small, then expands, as in a jug, would that be detrimental to successful cave spawns? can a cave be too long? is there an optimal angle for a cave? horizontal? sloped slightly upwards? or maybe NONE of these things are critical and plecos are opportunistic and will make do with anything remotely suitable?

Sorry, I know these answers will vary from species to species... but I'm wondering if there's any such information, anywhere, for any species.

one last question... is poop build-up an issue? or does the dad keep the cave clean? i'm wondering if a jug-shape would result in poop build-up, and therefore ammonia build-up.

[pleco_breeder]

I use both PVC pipe, and PVC "jug shaped" caves for most plecos with no problem. For most Ancistrus species, I use vertical caves made from either PVC or terracotta pots making sure to leave a lip below the entrance to keep eggs from getting kicked. The males will keep the cave clean regardless of dimension unless you go out of your way to make a place for it to get trapped intentionally.

Larry

[wijnands]

I've got this one which is roughly D shaped


And I've got a circular one where noone has shown any interest in.

[DKcincy]

...I use vertical caves made from either PVC or terracotta pots making sure to leave a lip below the entrance to keep eggs from getting kicked....
Larry

Vertical or horizontal? I'm having a tough time imagining a vertical cave.

A few days ago I started trying different shapes & sizes in my tank. The plecos enjoy anything cave-like. But I'm wondering if they'd actually spawn in some of these odd things.

I really like that D-shape cave. I don't have any like that yet.

[wijnands]

I'm sure you can make a deal. http://www.legholen.com/adresgegevens/ Is where I got them. Site's in Dutch but I'm sure she speaks english

[DKcincy]

Here's a unique piece I'm going to try as a pleco cave. the whole length is 10in(25cm). the length of the tube is 6in. this should be interesting!

[pleco_breeder]

...I use vertical caves made from either PVC or terracotta pots making sure to leave a lip below the entrance to keep eggs from getting kicked....
Larry

Vertical or horizontal? I'm having a tough time imagining a vertical cave.

The easiest way to explain this, is the ones I use for common Ancistrus. I use a four inch flower pot flipped upside down. I seal the hole in the bottom, normally used for drainage, with either silicone sealer or a hot glue gun. I then cut a hole in the side, just above the lip, just slightly larger than the males horizontal and vertical dimensions. They will choose this over PVC every time. In the experiments I've done to allow them to decide for themselves, the females will usually fight to see who gets to live inside the PVC and who is stuck hanging out underneath it. The male always goes for the pot.

For claro, I'm currently trying a similar design using a two inch PVC cap. The males aren't as enthusiastic about these, but still consistently choose them as the spawning site. I think something about the bright white is deterring them from hanging out in them constantly as is the case with the inverted flower pots. Prior to this, I was cutting the end off of the same size pots as used for commons, and cutting a small hole in the side.

Larry

[ErikO]

Larry,

How are you cutting the hole?

Thanks,

Erik

[pleco_breeder]

I use a dremel with the fiber reinforced blades for the cheap dollar store pots. For the more dense stuff, I usually start a rough outline with a drill and masonry bit. Important to keep the piece cooled while drilling. For that, I normally just support it in a shallow container of water and drill slowly.

Larry