Can Clown Pleco (L104) and Flyspeck Hardyhead Live Together?

Reviewed by Guidarium Editorial DeskUpdated April 30, 2026
Possible with Caution

Keeping Clown Pleco (L104) and Flyspeck Hardyhead together is possible but requires caution due to potential behavioral clashes. Provide a spacious tank of at least 75 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Clown Pleco (L104)

Panaqolus maccus

Flyspeck Hardyhead

Craterocephalus stercusmuscarum

🐠Family Group
Clown Pleco (L104)
Catfish
Flyspeck Hardyhead
Other
Temperament
Clown Pleco (L104)
Mostly Peaceful (3/10)
Flyspeck Hardyhead
Peaceful (1/10)
Temperature
✓ Compatible
Clown Pleco (L104)
23–28°C
Flyspeck Hardyhead
22–28°C
pH Range
✓ Compatible
Clown Pleco (L104)
6–7.8
Flyspeck Hardyhead
6–8
Hardness (dGH)
✓ Compatible
Clown Pleco (L104)
4–15
Flyspeck Hardyhead
5–15
Water Type
✓ Compatible
Clown Pleco (L104)
Freshwater Only
Flyspeck Hardyhead
Freshwater Only
Flow Preference
✓ Compatible
Clown Pleco (L104)
Moderate
Flyspeck Hardyhead
Moderate
Min Tank Volume
Combined: 75 L
Clown Pleco (L104)
75 L
Flyspeck Hardyhead
75 L
Swimming Level
✓ Different zones
Clown Pleco (L104)
Bottom
Flyspeck Hardyhead
TopMiddle
🏷️Behavior Tags
Clown Pleco (L104)
Shy / Slow Moving (Easily Stressed)NocturnalTerritorial (Defends specific area)
Flyspeck Hardyhead
Hyperactive / Fast SwimmerJumper (Lid Required)
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Can your tank handle Clown Pleco (L104) and Flyspeck Hardyhead?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Clown Pleco (L104)
Flyspeck Hardyhead
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Behaviour & Temperament

Clown Pleco (L104) is a generally mild-mannered species (3/10), while Flyspeck Hardyhead is peaceful (1/10). This modest difference means Clown Pleco (L104) may occasionally assert dominance over Flyspeck Hardyhead.

In terms of spatial distribution, Clown Pleco (L104) prefers the Bottom (Substrate) zone, whereas Flyspeck Hardyhead occupies the Top (Surface) and Middle (Open Water) zones. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Clown Pleco (L104) is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Flyspeck Hardyhead is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Clown Pleco (L104) and Flyspeck Hardyhead to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

Water Parameters

The safe temperature window for both species falls between 23°C and 28°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

Both fish can tolerate a pH between 6 and 7.8. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Clown Pleco (L104) and Flyspeck Hardyhead together, plan for an aquarium of at least 75 litres with a minimum length of 60 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Driftwood (Digestion/Hiding), Plants - Densely covered, Established Algae (Otocinclus). Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.

Why This Pairing Needs Extra Planning in Practice

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Clown Pleco (L104) and Flyspeck Hardyhead need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Clown Pleco (L104) and Flyspeck Hardyhead.

Show 17 more tank sizes

Frequently Asked Questions

Can Clown Pleco (L104) and Flyspeck Hardyhead live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 75 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Clown Pleco (L104) and Flyspeck Hardyhead need?

A minimum of 75 litres (tank length at least 60 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Clown Pleco (L104) and Flyspeck Hardyhead together?

Keep the aquarium between 23°C and 28°C. A target of around 25.5°C sits comfortably within both species' preferred ranges.

Are Clown Pleco (L104) or Flyspeck Hardyhead aggressive?

Clown Pleco (L104) is generally mild-mannered (3/10) and Flyspeck Hardyhead is peaceful (1/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Clown Pleco (L104) and Flyspeck Hardyhead need?

Both species overlap in the 6–7.8 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

How do I manage Clown Pleco (L104)'s territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Clown Pleco (L104) space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

Does Clown Pleco (L104) being nocturnal affect compatibility?

Clown Pleco (L104) is most active after lights-out, which naturally reduces daytime encounters with its tank mate. This can actually be beneficial, as both fish get undisturbed time to feed and explore. Just ensure food reaches Clown Pleco (L104) during evening hours.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
April 30, 2026
Last updated
April 30, 2026
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