Crabitat: Plant Guide - Questions and General ‘how to’

[aussieJJDude]

INDEX

Intro/ FAQ - here
‘Terra-’ or ‘viva-’: which ‘-rium’ is correct?

Source of Plants - where do I get plants from?
Plant requirements - what do I need to keep plants happy?
Substrate - what is best?
Watering Plants
Lighting - what type of light do I need?
Why keep plants with crabs?
Fertilisation - do I need it?
Plant List - what can be added?
Plant Related ideas - extras/misc....

We all love the idea of adding plants as an enrichment tool for our cute little clawed friends (and lets be real here, they certainly look a lot nicer than any plastic plant). Since most crabbers tend to come from aquarium, vivarium (or gardening) hobbies, the idea of trying to simulate the natural ecosystem within our crabitats it's certainly intriguing.

The issue is that unlike the aquarium and vivarium people, hermit crabs tend to be the ‘forgotten child’ where there's not a lot of information out there on keeping plants in a hermit crab enclosure, which makes it difficult to consider turning the crabitat into a planted paradise. Which isn’t surprising, the typical crabitat is hard to create a fully functioning bioactive setup.

When keeping plants, I tend to view basic knowledge on plant biology as vital to ensure success within the crabitat. This doesn’t mean to go out and become a botanist (but by all means, go right ahead!), but cracking open those dusty high-school biology books or google-fu to understand concepts like photosynthesis and plant nutrition is certainly going to help ensure that you start out on the right foot.


A hermie playing on a Bromeliad (Aechmea sp.)

FAQ
*to be placed here*
(If anyone has a good FAQ that worth adding, feel free to message a member of staff so it can be included in here.. Currently I can't think of any - kinda stumped tbh )

[aussieJJDude]

Within the ‘tank’ communities, the terms terrarium and vivarium get thrown around quite a lot, which for whatever reason, has different connotations to the actual definitions. The people of the internet have classed terrariums (‘terra’ meaning earth) as animal enclosures that tend to contain no living plants. While on the other hand, a vivarium (‘viva’ meaning life) usually refers to a type of terrarium that also contain plants, and usually regarded as being ‘bioactive’.

A bioactive setup, crabs with moss and isopods/springtails (isopod bottom right)

‘Bioactive’ is used to describe enclosures that replicate nature, by being self maintaining and cleaning. These enclosures usually contain microfauna that break down waste, such as isopods and sprintails, which in turn the waste from the microfauna is used to feed plants. One of the ultimate goals when planting an enclosure is to achieve the harmonious state of ‘bioactiviness’. While a bioactive setup is usually used in conjuction with plants, it is certainly not required... So it will not be included within the plant guide.


So, for many, their crabitats would be regarded as a type of terrarium. However, the introduction of plants, their crabitat would be regarded as a vivarium to many. (Hence, all vivariums are terrariums, but not all terrariums are vivariums. )

Stemming from this, there are many other types of ‘-riums’ out there. The vast majority is not applicable to land hermit crabs, since they do not offer the ideal setup for the crabs survival. Setups like aquariums, ripariums and paludariums should ultimately be avoided in anything but the largest enclosure where the crabs have areas that suit their needs - land; as well as deep substrate of the right consistency to burrow.


Aussie's previous 64g, no live plants (considered a terrarium)


Aussie's current 65g, with live plants (considered a vivarium)

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As for actual definitions of terrarium and vivarium, scientific literature views tends to differ a lot from internet groups. This is due to a terrarium typically only containing plants, and while animals may be present in the setup, they not required for an enclosure to be regarded as a terrarium. On the other hand, a vivarium usually refers to an enclosure that houses animals.

[aussieJJDude]

Ultimately, this will depend on the individuals location and where they feel they get the best deal from. Thankfully, for the most part, plants are easy to source. Some areas are likely to have a greater range and selection of plants, but common places to get plants for your tank can include:

• Your own ‘garden’ plants (many indoor and outdoor garden plants do well in a tropical environment, or originate from tropical areas and do well in the tank)
• Neighbours/friends/family (people close to you grow plants that's suitable for planting within the tank; offering a spare cutting or ‘baby plant’)
• Speciality vivarium stores (online stores cater to ‘vivarium’ hobbyists, and useful source of ‘ready to go’ plants for the crabitat)
• Online stores (think places like ebay and craigslist, also plant orientated forums may have suitable ‘crabitat plants’)
• Retail (both gardening/home improvement stores, but some grocery stores may also sell plants)

For me, I usually to have a look around at various stores to find all the options available. What usually is the deciding factor tends to boil down to personal preference of the type of plant I'm looking for; but usually ease, growing conditions and price tend to be my priorities.


Blurry pic showing some broms in a quarantine setup

Depending on the source, its normally a good idea to ‘quarantine’ a plant for a period of time before introducing to your crabitat. This is especially important if you have no idea on the growing conditions the plant (or cutting) was in prior to bringing it home. Not only does it allow you to inspect for pests, but allows a period of time to wash off any traces of insecticides or fertilisers that the plant was exposed to. Usually a period of a couple of weeks after being transferred to an organic media (EE or water are two great choices, with all parts of the plant washed thoroughly) will allow for the plant to be regarded as ‘crab safe’. As for plants with thick, or woody stems, I’d recommend up to a couple of months before introducing to the crabitat. Of course, during quarantine time, no exposure to pesticides or ‘un-natural’ fertilisers should be used.

Nothing fancy is needed for the quarentine setup. Due to bromeliads being a tropical species, I kept them in a small spare glass aquarium sealed with cling wrap and a LED bulb to keep them happy with a thin layer of moss for moisture. Some of my other plants I've simply kept on my desk and treat them as a regular household pot plant until quarantine has finish. You don't have to go overboard with quarantine, but if possible, try and keep it enclosed to reduce the chance of access for pests. A small vase, tote, spare aquarium or plastic container works wonders; located on a windowsill or under a small bulb to keep them happy.

[aussieJJDude]

Generally speaking, plants are not fussy. Their requirement of care comes down to the particular species chosen (sometimes even variety), so it grows without saying, research care requirements thoroughly. For most of us, we want the plant to survive with our clawed friends, so prior research to ensure the plant does well within the crabitat is always a good idea. (Another useful time for some google-fu or a gardening book that includes that particular plant; and youtube videos are a great source for quick and easy care requirements of most household plants!).

The requirements of plants once again, depends on the plant, “tHey aLL inDIVidUaLs”... Speaking for the majority of plants; substrate, water and light are three key ingredients to keep them happy.


A crypt (Cryptocoryne sp. ) and christmas moss (Vesicularia montagnei) in a seperate paludarium, that has water, lights and substrate (the moss) growing happily out of water; nothing fancy needed

[aussieJJDude]

Most likely, your plant is going to want a substrate to root around in. So, what makes a good substrate? The first and foremost thing is that it is crab safe, so try and stick with tried and true methods that we know are regarded as crab friendly. So, I’d avoid potting mixes and garden soils for two primary reasons: often contain additives in which *may* be crab safe, is certainly not proven and can often introduce pests. The best type of substrate (in my humble opinion! ) is:

• EE (coconut fiber) or peat fiber; and coconut chunks (these tend to mimic soil rather well, and useful for water retention around the roots while ensuring its relatively free draining. The addition of chunks to fiber I find is useful to increase texture in the ‘soil’, and help form good drainage to ensure the roots don’t get overly saturated)
• Worm castings (a good nutritious medium that the plants love, and is also crab safe)
• Sphagnum moss (not a good stand alone, but mixed in other mediums forms a good retention of water and decreases compaction of soil)
• Sand or gravel (not preferred as the only medium for plant, due to containing very little nutrition for plants, it’s practically inert. But very useful for free draining media, as water tends not retain around the roots)
• Water (useful for plants that are aquatic, or do fine in a soilless setup. These types of plants do best in a small bottle or the freshwater pool, and useful for water purification)
• None (some plants such as tillandsia have no roots, and don’t fair well being buried. For these types of plants, they are simply glued/wedged onto decor, where at most a bit of moss is used around the base depending on the species)

The substrate mix I use (mostly EE with coconut chunks with small amounts of coral sand, coral rubble, moss and gravel)

A valid question for plant plants (aka, have roots and grow in some type of ‘soil’) is whether to plant in the crab substrate or within a pot. IMO, keeping the plants in pots would be preferred. Not only does it since it does contain the roots (which shouldn’t be a problem for the crabs anyway) but crabs do enjoy eating plants, which can extend to the roots. Likewise, many crabbers moisten their substrate with salt water initially to curb mould growth, which salt can kill most species of plants. Keeping the plant in a small pot will reduce the likelihood of the plant coming into contact with the salt. Plus it makes soo easy if the plant simply isn’t doing well in the tank, simply remove, which less disruptive on the moulting substrate (and potential crabs).


A Tillandsia (T. ionantha 'pink beauty') that simply wedged onto a peice of wood (moss is not required)

As for the type of pot, it doesn’t have to be a fancy terracotta moment. A simple plastic pot or plastic or glass container that’s at least a couple of inches deep is fine to use for most plants.


Have buried plants straight into the substrate (plant in foreground is a Fittonia sp.) in the past (found they didn't last long; but could be due to using pure EE, a small incandescent bulb or simply not potted well)

[aussieJJDude]

Whether it has drainage holes (or not) ultimately boils down to personal choice. Keep in mind when watering, if you water a little too 'aggressively', water will pool at the bottom, which can lead to root rot, and plant death. So for ‘holeless’ containers, consider adding a layer of gravel/sand at the bottom for any excess water to pool - and water less! As for containers with holes, remember that too much water can flood your crabitat, especially if you are not careful with your watering regime. A good idea would be to consider a false bottom or regularly test the substrate for pooling water by making a small ‘tunnel’ out of a ruler/chopstick/pen and observe if water pools within the void of the ‘tunnel’.


I only water around 10-15 ml for each plant every couple of weeks

So err on the side of too little water, rather than too much. Plants need less water than you would think! For most plants, try to aim to water the plant every couple of weeks. I find it handy to use a small plastic syringe or turkey baster and squirt each plant once, usually less than 30ml works well for most plants. Of course, the watering regime will ultimately depend on the type of plant and the tank setup!

I usually like to water my plants when I notice them being ‘thirsty’, which signs to look out for are usually droopy leaves, wrinkling of ‘thick’/’succulent’ leaves or for some plants, folding up leaves or loss of leaf (turning brown). It’s important to keep in mind that I find droopy leaves can also mean a plant is overwatered, which usually can mean browning/blackening of the plant parts, breakage of parts and sometimes mould growth.

The best type of water would be dechlorinated tap water, which should keep most plants happy. This is likely to have dissolved compounds which the plant can utilize, and give the plant a little boost that bottled, distilled or spring water likely lacks. A good idea is to save the dirty water from the freshwater pool, and use the water from that to water your plants!


Humidifier on a timer also waters my plants, since the EE naturally absorbs drops of water which spreads across my background (which reduces the need to water my plants)

[aussieJJDude]

Plants require light.
This is what they use to photosynthesize. The type of lighting unit you require varies based on the plants you intend to keep. Some plants require extremely low lighting conditions, others require very bright lights… so not to beat a dead horse, research the plant to see if the intended light will suit (or vise versa). Basically plants use two specific parts of the colour spectrum for photosynthesis (400 - 700 nm) in which chlorophyll is able to use energy from the light for cell growth and reproduction. Most commercial lights will include this colour spectrum, so no need to worry about finding lights of a particular colouration.


Small spider plant (Chlorophytum comosum) not looking well due to not having a light

For most people the first point is to look at the Kelvin rating. Kelvin (measured in K) refers to the colour (also known as wavelength) the light will emit. Generally below 6000K, the light will appear to have a red hue (warmer), and about 12,000K, the light appears to be cooler (blue/violet). For most people, your ultimately looking for something around 6500- 8000K, which closely mimics natural daylight. Between 8000-10,000K, the light is closer to a bright white, typical of indoor lighting. While the kelvin rating is handy for being ‘aesthetically pleasing’, it is not useful in determining a suitable light for plant growth.

Ideally, you should look for the PAR (Photosynthetic Active Region). A high PAR is good for the plants, since it allows for the chlorophyll to work properly and efficiently. An increase in PAR is also useful to bring out colouration, size or shape in plants as well. Not all lighting units will have a PAR rating, but you can ‘guessitmate’ by wattage and/or lumens… A higher watt/lumen often correlates to a high PAR rating. If the light unit contains a PAR rating, numbers greater than 30-50 μmol/m²/s should keep most plants happy IMO

There are many choices out there; and if your DIY savvy you could certainly combine fixtures to suit your tastes. A brief breakdown:

• Light Emitting Diode (LED)
• T5/T8/T12
• Metal Halide (MH)
• Compact Fluorescent lamp (CFL)
• Sunlight (only work if you have a skylight, or well lit room… even then, supplemental light may be needed!)

In terms of ‘all round’ suitable for most setups, LED’s and T5’s would make a wise decision. There’s a lot of options out there; so useful if one has a budget, as well many lighting units have ‘fancy extras’ (like built in timers, gradual increase/decrease in light intensity during the day or settings that mimic storms) which can be fun to play around with. These two options also have an extremely low heat output in comparison to other lighting setups, which is especially useful in smaller tank setups. LED’s especially are energy efficient, so a very environmentally and hip pocket friendly choice.

My LED 6500K light setup for an aquarium (contains mostly white bulbs, but also blue, red, magenta and green for increased colouration)

Most lighting options can be found in places one would look to buy a light to keep a planted aquarium or vivarium; these lighting systems will work wonderfully for plants in the crabitat. Your local pet store, hardware store or online also have good options; and a quick dive on the internet (or recommended from another individual) is certainly helpful to make an informed choice.

MH should only be used in the largest of tank systems, or in an extremely deep crabitat where other lighting systems are likely not to be powerful enough in depths greater than 4 -6ft! They run very hot due to a very high wattage; and can quickly warm up small crabitats if not monitored closely. Ideally they should be avoided, but if your bent on going with MH, researched extensively for suitability!

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UVB systems aren’t required for optimal plant growth, so certainly not required to keep plants. All lighting systems mentioned above will emit UVA (and at most, minute traces of UVB), so can also form a source of UV. Generally speaking, if one is interested in UVB supplementation, a specialised (separate) system is going to be required.

For further lighting queries, refer to the lighting guide: http://www.hermitcrabassociation.com/ph ... 26&t=92543

[aussieJJDude]

By no means an exhaustive list, but a few points of why it may be a good (or bad) idea to add plants within the crabitat.

Positive (+)

• Photosynthesis (removal of CO2 during the day)
• Can removal of toxic compounds (think ‘crab waste’ making a nice fertiliser for the plants)
• Intricate playground for hiding/climbing places
• Can be a food source
• A humidity source ( plants respire water)
• Visually pleasing
• Can removal of excess water from substrate/tank

Negative (-)

• Plants respire at night, competing with animals for oxygen (our tanks tend to be well sealed)
• May reduce substrate volume
• Some plants require specialist conditions
• Plants can be expensive
• Crabs may (will) destroy plants
• Stores may spray plants with ferts/pesticides (quarantine can be a PITA)
• Can introduce or attract other animals

[aussieJJDude]

This will ultimately depend on what type of soil you have, water (some water sources are high in mineral/nutrients that it will provide enough for plant growth) and the species of plant chosen. There's two main types of nutrients plants need, macro- and micro-nutrients. Lack of these nutrients ultimately lead to deficiencies, which usually leads to lack of growth, discolouration, death of plant and odd shaped leaves.

Macro nutrients tend to be offered in higher quantities to micro nutrients for optimal plant growth. For me, I find Potassium, Nitrogen and Phosphorus to be most critical for optimal plant growth. These three tend to be critical in maintaining healthy growth, and usually when one (Potassium, Nitrogen and phosphorus) is lacking, it becomes very apparent on the plant.


Macronutrient table: blue shaded elements the plants will already have these elements through air and water; green shaded elements are the more essential macronutrients

Micronutrients aren't readily required, and for most plants, tap water is able to keep levels high enough for plant growth. There are retail micro nutrient mixes available, which I find useful for increasing vigour and colouration of plants.


Micronutrient table

In most instances, the crabby excretions and normal tap water will provide enough to keep the plants happy or healthy, and maybe some of their uneaten foods decomposing. For plants that a heavy nutrient feeder (they fast growing) the best option would be to add some worm castings to the mix.


A java moss (Vesicularia dubyana) pit; fertilisation was crab poop, freshwater pool water and fish tank water

Aquarium fertilisers could also be used, since in a lot of instances they used in tanks that contain delicate freshwater invertebrates. It is important to mention that aquarium ferts aren’t commonly used with hermit crabs, so one would use these products at their own risk – but the risks should be minimal. I’d recommend diluting in some water, in a lower dosage rate (I’d recommend starting with half of the recommended dose) than on the packaging. If you go down this route, I would highly consider buying dry fertilisers instead of pre-mixed solutions. Dry mixing, you're able to tailor the dose to suit your plants.

For me, I use 2-3 mixes of dry ferts: A macronutrient mix ( K2SO4, KNO3, KH2PO4 & MgSO4) in conjuction to a micronutrient mix (Rexolin APX, and supplemental iron). I find this to work best on both my aquatic plants (where I dose weekly) to my hermit crab tank (dose monthly to every second month, heavily diluted)

With fertilisers, it can simply be offered every second to fourth watering. It doesn't need to be offered continuously.

[aussieJJDude]

Now we get to the good stuff – or you just scrolled past all of the other stuff and came directly here! It’s important before you decide to grab any old plant and pop it into the crabitat, you need to research thoroughly. Some plants are considered harmful to crabs – like lucky bamboo – and would not make a wise choice in the crabitat; others require conditions not suitable for crabs – like low temperatures or low humidity – to grow well and as a result; is best to steer away from. Likewise, some plants are difficult to care for and do not make the best candidate for starting out with a planted crabitat until one has gained further experience. (It far more rewarding to start with more forgiving plants and work your way up to difficult to care for plants than spend a lot for difficult plants that will die on you - or crabs will destroy!) Remember plants don’t have to be permanent fixtures to the tank, and are easy to swap out if you decide to ‘upgrade’.

There are three categories in which the plants have been sorted into:

• Great – these are plants that works well; have not regarded as harmful and/or highly successful in numerous crabitats long term
• Good – these are plants do fine; can be considered harmful to crabs (whether it is or not, well that owner’s choice, otherwise research extensively) and/or have limited success long term or only in a couple setups
• Bad – these are plants that it is regarded toxic; doesn’t work well in the crabitat and/or have no long-term success

If you happen to see a plant that is not on any one of these lists, feel free to make a post about it; in which members can discuss is suitability in the crabitat and potentially make its way to one of these 3 lists. If there is any additional information, it will be included alongside. These are my own thoughts and recommendations, others may have different views on the matter, where all plants on this list have been tested by other crabbers or at least myself.


The Great:

• Seed sprouts (chia, bird seeds)
• Broms (Neoregelia sp.)
• Broms (Tillandsia sp.) - *some tillandsia prefer dry conditions, research your chosen plant thoroughly
• Spider plant (Chlorophytum comosum)
• Mosses
• Orchid (Phalaenopsis sp, many other species available) - prefer to be ‘drier’, do well in a well-ventilated area, some are temperate species
• Ferns (except asparagus, refer to below) - most do well and grow reasonable sizes, maidenhair ferns like ventilation as water build up will cause rotting of leaves/stems
• Bamboo (Bambusoideae subfamily) - can grow big
• Palms (indoor palms especially) - can grow big
• Dandelions (Taraxacum sp.)
• Mangroves (Rhizophora sp., but other ‘mangrove plant genus’ can be used) - can grow large
• bromelioides Earth Stars (Cryptanthus sp.)
• Prayer plant (Maranta sp.)
• Pothos/Devil’s ivy (Epipremnum aureum) - contains oxalates, but many have kept with crabs successfully

The Good:

• Brom (Tillandsia sp.) - some varieties prefer drier conditions… Many brom hobbyists go with the rule of thumb if it has a ‘dusty’ covering, its not well suited to high humidity.
• Brom (Aechmea sp.) - can grow large
• Brom (Guzmania sp.) - can grow large
• Ficus (Ficus sp.) - releases irritating sap when broken, unknown if harmful to crabs
• Ponytail palm (Beaucarnea recurvata) - can grow large, prefer a ‘drier’ environment
• Monstera (Monstera sp.) - can grow large
• African Violet (Saintpaulia ionantha) - leaves are known to be an irritant for mammals
• Yucca (Yucca sp.)- prefer to be ‘drier’
• Philodendron (Philodendron sp. eg: P. xanadu, P. scandens) – most contain oxalates
• Asparagus fern (Asparagus aethiopicus)- toxic to mammals, contain sapogenins
• Ice Plant (Carpobrotus edulis) - a member has had some success, little long term results shown (http://www.hermitcrabassociation.com/ph ... 6&t=109038)
• Flame Violets (Episcia cupreata)
• Pilea (Pilea sp.)
• Nerve Plant (Fittonia sp.)
• Arrowhead vines (Syngonium sp. eg: S. podophyllum, S. angustatum) – oxalates
• Baby tears (Soleirolia soleirolii)
• Begonia (Begonia sp. eg: B. corallina, B. rex) - has oxalates and cucurbitacin B, some can also grow large
• Mondo grass (Ophiopogon japonicus
• Peperomia (Peperomia sp. eg: P. obtusifolia, P. prostrata, P. rotundifolia, ) - some grow large, or prefer drier conditions
• Calathea (Calathea sp. eg: C. orbifolia, C. zebrina) - some grow large
• Peace lilies (Spathiphyllum sp.) – oxalates
• Umbrella Tree (Schefflera sp.) – oxalates
• Cordyline (Cordyline sp.) – saponins, grows large
• Ivys (Hedera helix) - few have tried this, mixed success; also toxic to many animals
• ‘Aquatic species’ (most are bog/terrestrial plants used in aquarium) – some contain oxalates, limited knowledge of toxicity for many, most require access to constant moisture or very high humidity
• Tropical Succulents (like Rhipsalis sp., Crassula ovata, Aloe sp., and Schlumbergera sp.)
• Hoya (Hoya sp.)
• Wandering Jew (Tradescantia sp. eg: T. pallida, T. zebrina) - unknown irritant for cat/dog, mixed views on toxicity for cat/dog

The Bad:

• Dracaena/Lucky Bamboo (Dracaena sp. eg: D. fragrans, D. reflexa, D. draco, D. sanderiana) - steroid saponins, known poison to mammals, however some have had them with crabs with no ill effect; some also grow large
• Succulents – most will not respond to well high humidity
• ‘Evergreens’ (loose term, like pine) - more temperate species; also contains isocupressic acid

Most of the plants from the first 2 should be safe enough to keep with crabs, many crabbers who keep crabs will plants have noted that they will stay away (not eat) from some plants if they have a known toxicity.



I tend to go with the school of thought, if its reptile/amphibian/fish safe, it should be crabs safe. Generally they are likely to have little to low toxicity, and do well in warm/humid environments.

[aussieJJDude]

Some of the below ideas are ways one can either incorporate plants, or perhaps care for plants thats slightly more demanding and require additional conditions to be happy. Of course, this is not an exhaustive list, and can be mixed/matched to suit budget, design of the tank and goals of keeping plants.


A previous jungly looking setup (in a 140g) complete with a dead looking maidenhair fern (Adiantum sp.) (Other plants include - left to right - a prayer plant (Maranta sp.), wandering jew (Tradescantia pallida 'purpleheart'), Calathea (Calathea orbifolia), orchid (Cymbidium sp.), button fern (Nephrolepis cordifolia) and a fittonia (Fittonia sp.)

• Add a fan, some species of plants enjoy air circulation; but also useful to decrease stagnant air in the enclosure. Plus, it adds a nice little breeze that the crabs may enjoy playing with!
• Add a timer to control the photoperiod and turn off/on the lights for you, allowing you to enjoy the tank and allow the crabs to enjoy a consistent day/night light cycle.
• Add a misting/fogging system; useful in watering the plants, but also allows one to increase the humidity of the enclosure. This is best used in conjunction with a false bottom/bulkhead to remove standing water from the substrate…. The crabs may enjoy natural weather simulations!
• DIY 3D background to grow plants on or around, not only is it a fun process but is highly customisable! Crabs enjoy these a lot, but may not be suitable for UTH, but can give you choice in size and placement of levels, caves, plants ect..
• DIY lights (eg: using flood lights, or making your own system) which can be cheaper, easier to put together, making easier to simulate day/night/weather cycles)
• Addition of aquatic plants in the freshwater pool (or emersed); since most of the aquatic plants are actually terrestrial, and interesting as they have different leaf growth, colour and/or patterning to submerged growth, and good for water quality of freshwater by removing pollutants from the water
• Cool climbing ornaments (using creepers/vines, some wood, egg-crate, something strong and crab safe) and allow the plant to grow over; allowing crabs plants more areas to climb over; form a nice canopy for the crabs to hide in and have fun playing around in

Crabs also enjoy playing in the mist of the humidifier, I call that a win/win