Sete Quedas eartheater

Where they come from

Gymnogeophagus setequedas is one of those southern South American eartheaters that makes you fall in love with substrate-sifting cichlids. They come from the Uruguay River basin region around the old Sete Quedas area (the big falls that used to be a landmark before dam projects changed the river). Think cooler seasonal water, sandy stretches, scattered rocks, and a lot of natural grazing.

They are not a "hot Amazon" fish. If you keep them like a typical warm-water community cichlid, they will usually survive, but they look tired and get finicky long-term.

Setting up their tank

Give them floor space and sand. That is the whole game with these guys. They spend a ton of time taking mouthfuls of sand, sifting it, and spitting it out like little bulldozers.

• Tank size: I would start a pair in 40 breeder territory, but a small group really wants 75+ so they can sort out pecking order without one fish getting pinned all day.
• Substrate: fine sand (play sand, pool filter sand, or aquarium sand). Skip sharp gravel. They will still try to sift it and you can end up with mouth damage.
• Hardscape: smooth rocks, rounded river stones, and a few pieces of wood. Make broken sight lines so a chased fish can duck out of view.
• Plants: doable, but choose tough stuff (Anubias, Java fern) and anchor it to wood/rock. Rooted plants get redecorated.
• Filtration: they are messy sand-sifters. Use more mechanical filtration than you think and rinse it often.

Water-wise, aim for clean and well-oxygenated. They appreciate cooler temps than most cichlids. I have had the best results keeping them in the low-to-mid 70s F. They can handle warmer for short periods, but I would not park them at 80+ year-round.

Feeding

They eat like classic eartheaters: a mix of small meaty bits and whatever they can graze from the substrate. In my tanks they do best on smaller foods offered a bit more often rather than one big sloppy feeding.

• Staples: a good quality cichlid pellet (smaller size), supplemented with flakes or granules they can pick up off the sand
• Frozen: bloodworms, brine shrimp, daphnia, mysis (rotate, do not make bloodworms the whole diet)
• Occasional: live foods if you trust the source (blackworms, live brine) - great for conditioning
• Veg matter: they are not strict herbivores, but a little spirulina-based food or blanched veg now and then keeps things moving

Behavior and tankmates

They are generally on the calmer end for cichlids, but they still have cichlid attitudes. Most of the time they are busy sifting sand and doing little fin-flares at each other. During spawning, they get a lot more serious about personal space.

In a group, you will see a pecking order. That is normal. What you do not want is one fish getting hammered constantly with no breaks. That usually means the tank is too small, too bare, or the group is unbalanced.

• Good tankmates: other peaceful-to-moderate South American fish that like similar temps (dither tetras that can handle cooler water, robust bottom fish that will not be bullied easily, some loricariids if you have hiding spots)
• Avoid: hyper-aggressive cichlids, fin-nippers, and super delicate fish that panic at every display
• Also avoid: tiny shrimp and anything you cannot afford to have sifted, chased, or snack-tested

Breeding tips

If you have not kept Gymnogeophagus before, the fun part is they are typically maternal mouthbrooders. You will see them pair up, clean a spot (often a flat rock or a cleared patch of sand), and then the female will take the eggs into her mouth after fertilization.

• Conditioning: heavy water changes and lots of varied frozen/live foods usually flips the switch
• Spawning sites: offer a few flat stones and open sand areas so they can pick a spot
• After spawning: the holding female may eat less and get shy - give her cover and keep the tank calm
• Raising fry: once released, fry take baby brine shrimp and finely crushed foods well; gentle filtration and clean water make a big difference

Common problems to watch for

Most issues I have seen with setequedas come from two things: warm, stale water and dirty substrate. They are sand-sifters, so whatever collects in the sand eventually gets pulled through their mouths and gills.

• Mouth/gill irritation from sharp gravel or filthy sand: switch to fine sand and keep up with maintenance
• Bloat and stringy poop: often food-related or stress-related - cut back, add roughage, and check aggression
• Hiding and not eating: frequently temperature too high, tank too bright/bare, or a bully in the group
• Hole-in-the-head style issues: usually show up when water quality slides and diet is narrow - step up water changes and vary foods

If you get the sand, the space, and the cooler clean water right, they are honestly pretty forgiving for an "intermediate" fish. You will spend more time watching their little sand-spitting routines than troubleshooting problems.