Keeper timer setting
T5 UVB: one hour later on, one hour earlier off
ON: 1 hour after the daylight lights come on.
OFF: 1 hour before the daylight lights go off.
October: daylight 11 h 55 m; T5 UVB 9 h 55 m per day.
The T5 runs for two hours less than the total photoperiod. Example: daylight 08:00-20:00 means UVB 09:00-19:00. Keep the monthly UVI strength as listed beneath the tube. Existing care values are preserved.
UVI beneath the optional T5 tube
Working exposure targetOctober target at normal back height
UVI 3directly under the tube when it is on
The retained range remains a provisional captive working target. No new species-specific result was found that clearly requires a numerical change. Retaining it is not certification of an experimentally established optimum.
Your measuring point
Measure at the animal's normal back height directly beneath the brightest accessible part of the T5 strip, positioned toward the middle/back. The animal can enter and leave this area freely.
Keep a lower-UVI gradient and fully covered refuges near UVI 0. This is the optional exposure area, not the average across the cage.
Use a UV Index meter, such as a Solarmeter 6.5/6.5R. Warm the tube for about 30 minutes; keep reflector, guards and mesh in place. Raise or lower the fixture within its manufacturer's minimum-distance guidance, then recheck the reading and every higher accessible surface.
Evidence level: Provisional retention. These are working recommendations, often inferred; exact species optima and seasonal UV dose usually have not been measured. Log lamp-on time and animal behaviour as well as UVI.
Baines et al. (2016), UV-Tool ยท Muryn, Baines and Dishman (2026), Reptile Lighting Guide V10
October management
Selected automatically using the Netherlands date
Late laying / recovery
Tropical lowland dry and moist forest beside rivers, streams and other waterways - Central America into northern South America
27-30 CDay ambient
23-24 CNight
37-40 CBasking
3T5 UVI*
11 h 55 mPhotoperiod
9 h 55 mT5 UVB duration
70-85 / 85-95%RH day / night*
Mist 1-2x/day; pool alwaysSpray / water
4Food*
Annual schedule
Scroll sideways on smaller screens
| Month | Day ambient | Night | Basking | T5 UVI* | Photoperiod | T5 UVB duration | RH day / night* | Spray / water | Food* | Seasonal management |
|---|---|---|---|---|---|---|---|---|---|---|
| January | 26-29 C | 22-24 C | 36-39 C | 2-3 | 11 h 35 m | 9 h 35 m | 60-75 / 80-90% | Light mist daily; pool always | 3-4 | Dry season / low laying |
| February | 26-29 C | 22-24 C | 36-39 C | 2-3 | 11 h 45 m | 9 h 45 m | 60-75 / 80-90% | Light mist daily; pool always | 3-4 | Conditioning |
| March | 27-30 C | 22-24 C | 37-40 C | 3 | 12 h | 10 h | 65-80 / 85-95% | Mist 1-2x/day; moist nest | 4-5 | Breeding begins |
| April | 27-30 C | 23-24 C | 38-40 C | 3 | 12 h 15 m | 10 h 15 m | 65-80 / 85-95% | Mist 1-2x/day; moist nest | 4-5 | Courtship / mating |
| May | 28-31 C | 23-25 C | 38-41 C | 3-4 | 12 h 30 m | 10 h 30 m | 70-85 / 90-95% | Daily rain/mist; pool always | 4-5 | Wet season / laying |
| June | 28-31 C | 24-25 C | 38-41 C | 3-4 | 12 h 40 m | 10 h 40 m | 70-85 / 90-95% | Daily rain/mist; moist nest | 4-5 | Laying / incubation |
| July | 28-31 C | 24-25 C | 38-41 C | 3-4 | 12 h 35 m | 10 h 35 m | 70-85 / 90-95% | Daily rain/mist; moist nest | 4-5 | Laying / incubation |
| August | 28-31 C | 24-25 C | 38-41 C | 3-4 | 12 h 25 m | 10 h 25 m | 70-85 / 90-95% | Daily rain/mist; pool always | 4-5 | Incubation / hatching |
| September | 28-31 C | 23-25 C | 38-41 C | 3-4 | 12 h 10 m | 10 h 10 m | 70-85 / 90-95% | Daily rain/mist; moist nest | 4-5 | Laying / hatching |
| October | 27-30 C | 23-24 C | 37-40 C | 3 | 11 h 55 m | 9 h 55 m | 70-85 / 85-95% | Mist 1-2x/day; pool always | 4 | Late laying / recovery |
| November | 27-30 C | 22-24 C | 37-40 C | 2-3 | 11 h 40 m | 9 h 40 m | 65-80 / 85-95% | Mist daily; pool always | 3-4 | Wet-to-dry transition |
| December | 26-29 C | 22-24 C | 36-39 C | 2-3 | 11 h 30 m | 9 h 30 m | 60-75 / 80-90% | Light mist daily; pool always | 3-4 | Dry season / recovery |
Keeper notes
Use measured gradients and animal behaviour, not single thermostat readings
T5 UVI measurement
Measure UVI at normal back height directly beneath the brightest accessible part of the optional T5 strip. Place the strip toward the middle/back with free access to and away from it; preserve a gradient into fully covered refuges near UVI 0. These numbers describe the exposure area, not the whole enclosure or a daily average.
UVI review
The retained range remains a provisional captive working target. No new species-specific result was found that clearly requires a numerical change. Retaining it is not certification of an experimentally established optimum.
Habitat and enclosure
A fast territorial riparian basilisk of tropical lowland dry and moist forest. For one adult use about 180 x 90 x 180 cm or larger; breeding groups need substantially more room, ideally 240 x 120 x 200 cm or more. Provide strong branches, dense visual barriers and multiple escape routes. Never house adult males together.
Swimming water
Provide permanent water large enough for full submersion, turning and short swimming, with broad easy exits and branches over the water. Filter strongly, remove faeces promptly and change water frequently. Avoid warm stagnant pools.
Heat and UVB
Maintain active-season air around 27-31 C with cooler shaded zones and a strictly local 36-41 C basking surface. Use measured linear UVB; UVI about 2-3 at the main basking perch, with the option of a broad area approaching 4, is a conservative operational starting target.
Seasonality
Do not brumate. Use rainfall and humidity as the main seasonal cue: a slightly drier December-February phase, rising rain from March-April and a prolonged wetter breeding season from roughly May-November. Adults remain warm and feeding year-round.
Diet
Animal-biased omnivore. Field summaries report about 78% animal and 22% plant material in Panama. Rotate gut-loaded roaches, crickets, locusts, silkworms, earthworms and occasional snails; adults can also receive edible flowers and modest soft fruit. Juveniles are more insectivorous.
Breeding and nesting
Breeding is reported to begin around March, with repeated clutches of roughly 2-18 eggs possible over much of the following ten months. Provide at least 20-30 cm of private, slightly moist diggable soil/sand before the breeding season begins.
Incubation
Published incubation ranges are roughly 55-90 days. A conservative captive starting point is about 28-29.5 C in evenly moist, aerated medium. Record each clutch and avoid pushing temperature higher simply to shorten development.
Keeper warning
Common basilisks are fast and easily startled; collision injuries to the snout are a serious enclosure-design risk. High humidity must be paired with ventilation, clean water and dry basking surfaces. Repeated clutches can rapidly deplete females.