Red Phantom Tetra (Megalamphodus sweglesi)

Red Phantom Tetra (Megalamphodus sweglesi, still widely searched as Hyphessobrycon sweglesi) is a small, warm-coloured South American tetra for peaceful planted aquariums. It has the classic phantom-tetra look: a neat high body, a dark shoulder spot and coloured fins that show best when the fish is settled in a group.

This page has been corrected around the Red Phantom identity. The accepted and current supplier-backed name is Megalamphodus sweglesi, while Hyphessobrycon sweglesi remains useful older trade and search wording. The fish should be chosen for a calm community, not as a rough or boisterous tetra.

Why Choose Red Phantom Tetra?

Red Phantom Tetras bring colour and behaviour without needing a large species tank. Their red to amber body tone looks strongest under gentle lighting, especially against plants, leaf litter, botanicals or a darker background. Males can display to one another with raised fins, while females tend to be rounder and more softly coloured. In a group this display behaviour gives the aquarium movement without the aggression associated with some brighter red tetras.

• Scientific name: Megalamphodus sweglesi
• Common names: Red Phantom Tetra, Red Phantom
• Older trade name: Hyphessobrycon sweglesi
• Adult size: around 3-4 cm
• Temperament: peaceful, social and best in groups
• Tank zone: middle water, with regular use of planted cover
• Best kept: in a group of at least 6, with 8 or more looking better

Tank Setup And Water

FishBase places this species in the Orinoco River basin of South America, with soft to moderately mineral freshwater and a cooler tropical range around 20-23 C. In home aquariums, stability matters more than chasing a single number. A mature, well-filtered tank with gentle flow, clean water and shaded planting is the right starting point.

A 60 cm aquarium is a sensible minimum for a small group, but a longer tank gives the school more room to spread out and display. Use fine plants, floating cover, wood or botanicals around the edges, while leaving open swimming room through the centre. Subdued lighting helps the red colour look richer and makes newly arrived fish less nervous.

Group Behaviour And Tank Mates

Red Phantom Tetras are social fish. Kept alone or in too small a number, they can look washed out and shy; kept in a proper group, they hold position more confidently and show better fin display. Males may posture, but this is normally harmless if the group has space and visual cover.

Good companions include other peaceful small tetras, pencilfish, rasboras, Corydoras, small peaceful catfish, dwarf cichlids that like similar water, and calm livebearers where the water parameters match. Avoid large predatory fish, very nippy tank mates or anything likely to outcompete them heavily at feeding time. Very long-finned slow fish need care, as with most active tetras.

Feeding

In nature, phantom tetras feed on small animal foods such as tiny insects, worms and crustaceans. In the aquarium, offer a fine flake or micro pellet as the staple, then rotate small frozen or live foods such as daphnia, cyclops, brine shrimp and mosquito larvae. Small meals are better than heavy feeds, and a varied diet helps colour and condition.

Watch the group during feeding. Red Phantom Tetras are quick enough to eat in mid-water, but they should not be kept with aggressive feeders that leave them hanging back. A healthy group should look alert, rounded through the body and interested in food without becoming bloated.

How Many Should You Buy?

Six fish is the minimum starting point, but Red Phantom Tetras are much more convincing in a group of eight to twelve. A larger group spreads attention between males, encourages natural display, and helps nervous fish stay visible. If the aquarium is large enough, buy the group together so they settle as one social unit rather than adding one or two fish at a time.

They work especially well as a mid-water feature school in a planted aquarium. Keep the aquascape open enough for swimming, then use plant thickets, wood or leaf litter zones as retreat areas. This balance gives confident display without leaving the fish exposed all day.

Buyer Fit And Common Mistakes

Choose Red Phantom Tetras if you want a gentle shoaling fish with warm colour rather than a high-speed, boisterous community fish. They are not a good match for tanks dominated by large cichlids, fin nippers or very hard-feeding barbs. They also should not be used to cycle a new aquarium. Give them a mature filter, stable water and a peaceful group of tank mates from the start.

The most common mistakes are buying too few, keeping the tank too bare, or using lighting so bright that the fish stay pale and cautious. A little shade, a darker background and varied small foods usually bring out better colour and behaviour than trying to force colour with heavy feeding.

Acclimation And Ordering Notes

Use the size selector for the current live options. Young Red Phantom Tetras can look more subtle on arrival, then deepen in colour after settling into planted cover with steady water and good feeding. Keep the lights low during acclimation, float and drip-acclimate carefully, and avoid adding them to a brand-new aquarium.

Red Phantom Tetra is shipped by our UK live-fish courier service when suitable livestock dispatch conditions are met. Orders are covered by our Live Arrival Guarantee, and first-time customers can use WELCOME10 when the code is active at checkout. For best results, prepare a mature planted aquarium and buy a proper group rather than a single fish.

Care Basis

This rewrite uses live Shopify data, Petra source media, FishBase species data and specialist aquarium references for Red Phantom Tetra. The copy keeps natural search language while removing old mixed-identity text and forced phrases that could confuse customers, Google snippets or AI assistants.