Can Black Molly live with Flash Pleco (L204)?
Caution — with care
Why
- Large size gap (Black Molly 4" vs Flash Pleco (L204) 20") — the bigger fish may eat the smaller one as they grow.
- No overlapping water hardness: Black Molly wants 12–30 dGH but Flash Pleco (L204) wants 6–7.5 dGH.
Sweet spot: both do well at 72–82°F and pH 7–7.6 — aim there.
Side-by-side
| Black Molly | Flash Pleco (L204) | |
|---|---|---|
| Temperature | 72–82°F | 72–82°F |
| pH | 7–8.5 | 6.5–7.6 |
| Hardness (GH) | 12–30 dGH | 6–7.5 dGH |
| Adult size | 4" | 20" |
| Temperament | Peaceful | Peaceful |
| Min tank | 30 gal | 125 gal |
Together, plan on at least 125 gallons.
How to make it work
- Add only full-grown adults — never juveniles, which will be eaten.
- Target the overlapping water-parameter range and acclimate slowly.
Sort it with: GH remineraliser → Aquarium Co-Op
Where to buy
- Black Molly: buy at Flip Aquatics · Flip Aquatics live-arrival guarantee
- Flash Pleco (L204): buy at Flip Aquatics · Flip Aquatics live-arrival guarantee
Live-animal shipping: add a heat pack below 50°F, expect weather holds above 90°F, and schedule delivery for a moderate week when someone can receive it promptly.
Build a full tank around this stocking →Everything compatible with Black Molly · …with Flash Pleco (L204)