Crimson Day Gecko – The Ultimate Guide

Crimson Day Gecko

The Crimson Giant day gecko or Phelsuma grandis is known for its defining features and beautiful coloration. In the reptile pet industry, it is also more commonly known as the Madagascan Giant Day Gecko, a species that has grown in popularity over the years. 

The history of this animal can be traced back to the 1870s when it was first discovered by scientists in Madagascar. They were identified as arboreal animal that by nature, spends most of their time in trees. 

The crimson day gecko is an arboreal lizard which lives in the humid forests of Madagascar. 

They normally live in rainforests or inhabited places having warm and humid conditions. You can often see them climbing on the walls and ceilings of buildings or in the branches of nearby trees.


Crimson Day Geckos have a vibrant skin color of green with red patterns running down their back. These red patterns running from the nostrils to the geckos’ eyes are some of the easiest ways to identify them. Just like other Day Geckos, they have beautiful bright colors, however, they can quickly darken when they are stressed or feel threatened. 

Male Giant Day Geckos can reach a size of 10 to 12 inches which makes them one of the biggest members of the gecko family. Females, on the other hand, are shorter compared to males,  usually reaching around 9 to 11 inches.

The estimated lifespan of a Crimson Day Gecko is around 10 years however they have been known to reach 20 years when provided proper care.

Days geckos, although a popular choice for gecko enthusiasts are not the best pet for beginners as they require a bit more care than Leopard Geckos, Fat Tailed Geckos and Crested Geckos, so ensure you do your research before choosing this species. 


In the wild, they climb on the branches of the trees to prey on insects, to get from one place to another and to avoid predators. 

Crimson Day Geckos can be extremely camouflaged when in their natural environment, which helps them to avoid predators and hunt food.  

The rainforest sustains the needs of the gecko as well as other animal species. However, because of the demands in the global market and the growing population, their natural habitat is slowly being compromised. Crimson Day geckos have seen numbers decreasing and are threatened due to illegal collection for the international pet trade. 


Giant Day geckos are great display animals for your home because of their vibrant colors and day time activity levels. 

When choosing the right enclosure for your Giant Day geckos, it’s important to choose a large, high enclosure to help replicate their natural environment, as well as giving them ample room to move around. Being an arboreal animal requires a higher enclosure rather than width or depth.

We really like the Exo Terra or Repti Zoo ranges, they are extremely popular and are often used for a wide range of arboreal geckos including Crested Geckos and Gargoyle Geckos.

The recommended minimum size of an enclosure is 18in length by 18in width and a 24 in height. This is the minimum size, and would only cater a single adult Giant Day gecko. 

For an additional gecko you should increase the size to around 18x24x24 inches.

Males are highly territorial and as a result must not be kept with other males. Keeping mature males together will result in fighting and eventually death.

You can keep a male with another female but it is important to monitor the behavior of both animals and watch for signs of stress. Stress is one of the biggest killers of reptiles kept in captivity.


The ideal temperature for Giant Day geckos is around 80 to 86 f with a hot spot of  90-95 f. This allows the geckos to move around and choose the temperature they need (thermoregulate)  At night, the temperature can go lower, down to around 75 to 80 f. 

A heat mat can be a great way to help in raising the temperature of the hotspot. You can monitor the temperature by using a thermometer gun or a digital thermometer which are both much more accurate than the older dial models.


The humidity level inside the enclosure should be 60-70%. This can be achieved by misting daily and placing a water dish inside the enclosure. Giant Day Geckos will often be seen drinking the water droplets from the leaves. 

An important note when creating a high humidity environment, you need to be careful not to make the enclosure too wet as this can lead to the formation of mold. Mold can be avoided with good ventilation by using screens or wire mesh,  as this allows the moisture to evaporate more easily. This is another reason why we love the Exo Terra and Repti Zoo vivarium ranges as they come with a mesh lid as standard.


Decorating your enclosure is necessary for the well being of the gecko. Placing branches or bamboo help to make their enclosure like their natural habitat and accommodate their natural routine of climbing and hunting.

Depending on the kind of enclosure you want to keep your geckos in, you can opt for live plants such as bromeliads, sansevierias, trailing pothos or orchids. Live plants help maintain humidity and also give a beautiful natural look to the enclosure. The downside is when it comes to cleaning the vivarium, as there is more to remove and will take more time and effort 


As we have already established, Giant Day geckos require higher levels of humidity. As a result, you should incorporate substrates that can retain moisture. The ideal substrates for this species are mulch, coconut chips, moss and orchid bark, all of which are available at any good pet store who sell reptile or amphibian supplies. We like to use a combination of X and Y in vivariums that are on display. 

Light Requirements

Giant day geckos need higher basking points compared to other geckos. They love sunlight so you should provide them with high-quality UVB lighting to keep them healthy. Quality lighting also helps to bring out the best color of your pet. 12-14 hours of daylight is recommended for this species.


Crimson Day Geckos are omnivores, feeding on both insects and fruits. 

In captivity, they are easy to feed, commonly feeding on brown and black crickets as well as locusts – all of which can now be ordered online or found in most pet stores. For the occasional treat, waxworms or mealworms can be offered in small numbers as they are fatty and harder to digest. 

Commercially bred insects will provide your geckos with good nutrition however, it is worth noting that you should always gut load live food prior to feeding to help increase the nutritional value of the prey.

Size of food 

When feeding your Crimson Day Geckos, the size of the prey must be less than the space between their eyes. You can follow this rough gauge to help you. 

Stage  Size of insects 
Hatchling ¼ inch 
Adults  ½ – ¾ inch

For the fruit aspect of the diet, the easiest way is to purchase the pre-formulated powders which simply require a small amount of water to be added. These powders are now widely available and are fed to many of the different omnivorous geckos such as Crested Geckos, Gargoyle Geckos and Day Geckos. 

These powders are also easily purchased online (normally more cheaply) or can be found in most pet stores. 


The health of your geckos greatly depends on the quality of their diet. Although a diet of insects and pre formulated food gives them a varied diet, there are vitamins and minerals that must be given in order to maintain healthy bones. Dusting their food with a trusted calcium supplement at every meal will ensure they maintain healthy bones.

How Often Should I Feed Them?

For hatchlings and juveniles, you can feed them once a day with a staple of insects. For adults, they can be fed every other day or 4 times per week. 

Although they will rarely drink from a bowl, hydration is important, so it is always worth providing a drinking bowl with clean water every day. 

Sexing And Breeding

When it comes to determining the sex of these geckos, it can be a little challenging to identify a male from a female as they both have adhesive scales around the vent that can be mistaken for femoral pores. Males, however, do tend to get much more enlarged pores as they age as opposed to females. Males also normally have a broader head compared to females as well as also being more colorful but this can be a hard factor to purely base the sexing on.

Before breeding your geckos, it is advisable to adjust the light cycle by reducing it to 8 hours as well as the temperature down to 75 to 80 degrees for 14 days. After this period of cooling, raise the light cycle back to 12 hours of light and the temperature back to 83- 86 degrees fahrenheit. This will encourage breeding and you will soon see the lizards mating.

Depending on the set up you have will determine if you remove the female(s) or if they live together normally. We like to introduce females to the males for a period of 7 to 10 days and once mating has occurred several times, remove them back into their own enclosures where they will go on to lay their eggs for the season.

Crimson giant day geckos lay a pair of eggs once every three to four weeks during the breeding season. They Usually lay their eggs in the base of the plants such as sansevieria or snake plants but they also lay eggs on the substrate or in a damp lay box if you provide one.

Once you notice the eggs, remove them (keeping them in the same position) and put them into incubation. Unlike many other geckos, Giant Day Geckos eggs are not glued, so they can easily be removed for incubation.

Eggs incubated at about 80-83 f will hatch in approximately  60 days.

Common Health Issues 

Metabolic Bone Disease

This disease is a direct result of calcium deficiency and poor exposure to UV light.


  • Swollen legs
  • Malformed head and jaw, 
  • Irregularity of the spine 
  • Seizures. 


If your gecko consumes any of the substrates in the enclosure such as soil, it may lead to impaction. To prevent impaction, use a food dish to separate the insects from the substrate and also choose a substrate that is unlikely to cause impaction.  


  • Lethargy or weakness 
  • Swelling of the stomach 
  • Loss of appetite 

Improper Shedding 

Improper shedding, although not a serious problem, is a result when the enclosure does not provide adequate humidity levels. Misting once a day can help your geckos shed properly.


  • Unshed skin is left on the body of the gecko. This should be removed since it can restrict blood flow, especially to the toes.

Final Thoughts

Giant day geckos are beautiful, unique members of the gecko family. They are fairly easy to keep and breed and make an amazing display piece in the home – they will almost certainly come up in conversation when people visit your home.

As with any pet, it is imperative that you educate yourself on how to properly look after them so you both get to enjoy this mini piece of Madagascar for many years to come.

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