New tank!

Kirrie · Post by **Kirrie** » Sat Dec 07, 2013 8:26 am

I currently have a 10 gallon tank with two crabs, but I will have a new 20 gallon for them by the end of the month! Im very excited to give them more room to run around, and also some new tank mates down the line. I was thinking about adding 2 or 3 more crabs, would 5 be too many for a 20 gallon? I will have UTH stuck on the back of the tank, large enough for a 60 gallon tank. The one I have on my 10 gallon is only big enough for a 20 gallon tank, thanks to my ignorance, but it keeps the tank around 80 degrees usually. I am going to start with 6 inches of eco earth substrate, but add more if needed. Before I buy everything though, would it be better to use sand rather than eco earth?Ive had my first crab since August, and the second one since September or October, but I haven't seen either one go down to molt, they just dig holes everywhere and sit in them, is this normal?

Tongue Flicker · Post by **Tongue Flicker** » Sat Dec 07, 2013 5:32 pm

5 for 20 gallons is okay provided you keep small-growing species with lots of platforms and climbing places.Sand mixed with coco fiber and pesticide-free garden soil is the best for substrate for any pet animal for me. All my pets except my sugar glider and my betta fish, are on this mix. Toss in a few isopods and springtails to start the natural earth cycle and you're good to go without ever having to replace the substrate, worry about odors or bits of uneaten food. In the reptile world we call this 'bioactive substrate'.It holds humidity very well and supports burrows perfectly.Hermits normally live in holes many feet below ground so that is perfectly normally.

Kirrie · Post by **Kirrie** » Sat Dec 07, 2013 6:08 pm

Thanks for replying!I have two purple pinchers currently and I plan to stick with purple pinchers for any new crabs I add. Would 5 of those be ok, or should I only keep 4?I like the idea of the bioactive substrate! Where can I find the things I need to create that though? Im pretty sure I can find the coco fiber, garden soil, and sand, but what about the isopods and springtails? Also, what sort of sand is safe for hermit crabs?Sorry I have so many questions, I just want to get this all figured out so I can set the new tank up as quickly as possible once I get it.

Tongue Flicker · Post by **Tongue Flicker** » Sun Dec 08, 2013 2:25 am

Temporarily, yes. They can grow quite sizeable and must be rehoused when they do.You're in the US so they're pretty easy to get. It's even available online. Isopods and springtails eat mites and decaying matter in the substrate.Play sand or washed beach sand is okay to mix. Just avoid sand that clumps and hardens or has sharp grains like black fluorite sand and stuff.

Kirrie · Post by **Kirrie** » Sun Dec 08, 2013 5:23 am

Ok, I will start looking around. Thank you

Crabber85 · Post by **Crabber85** » Mon Dec 09, 2013 7:44 am

@Kirrie, for a twenty gallon you can get away with three or four smalls or two mediums but in a year or so these crabs will have effectively double in size so the space that the enclosure offers now wont be there.You also have to factor in the size of the dishes, decor and climbing structure when deciding on the size of the crabs you want.Eco Earth is the superior substrate though play sand works well and as these are the only two types of substrate approved for use with hermitcrabs they are readily available however the play sand is by far the cheaper of the two.Any kind of soil such as potting, top or gardening should be avoided as these have fertilizers, metal shavings that the processing equipment leaves behind and other chemicals to promote plant growth which makes these substrates toxic at best.

Kirrie · Post by **Kirrie** » Mon Dec 09, 2013 8:01 am

I think the two crabs I have now are small to medium sized. As I upgrade my fish tanks, I can move my crabs into larger tanks, so there shouldn't be a problem with space down the road. I have a 29 gallon community that Id like to upgrade to a 55 eventually.This is probably a silly question, but how much do crabs grow each time they molt? Neither of my two have molted since Ive had them.The reason for the upgrade now is because there isn't much running space in the 10 gallon with all of the dishes and toys, as you mentioned. Im not too worried about cost right now because Im more worried about making sure the crabs are happy. Which of the two substrates is easier to care for, or better for the crabs? I cant remember exactly what I read, but I read that there could be problems with crabs molting in sand. Which is safer for a beginner to use?

Crabber85 · Post by **Crabber85** » Mon Dec 09, 2013 11:43 am

@Kirrie, I'm not sure where you heard hermitcrabs can have a hard time molting in sand as far as we know more than half of the currently sold species live on or near a beach which is where they molt so play sand is actually a much more natural molting substrate.Eco Earth is made from ground up coconut husks and as it breaks down it becomes acidic unlike the sand which is PH neutral and over time the EE can actually become so acidic that it can pose a risk to the soft exo of a newly molted hermitcrab though the process of building up a high enough acidity level takes so long that if your changing out your sub on a regular basis once every six months for enclosures under thirty gallons and once every twelve to eighteen months for larger enclosures you should never have a problem.It has been recommended that mixing play sand with ee in equal portions can slow down the build up of acidity in the substrate as the sand acts as a buffer much the same as coral or dolomite does to aquarium water.Hermitcrabs swell their new exo after each molt by drinking salt water so they grow a little after each molt and depending on the species they can double in size after two molts or four.Species like the purple pincher grow faster but molt less frequently than species like the Ecuadorian or E which molts often but doesn't swell up as much after each molt and so grows a lot a slower.

Geranium · Post by **Geranium** » Mon Dec 09, 2013 11:54 am

You may have been reading about calcium sand, which is not a suitable substrate. Playsand from the hardware store is what you want.

Kirrie · Post by **Kirrie** » Mon Dec 09, 2013 11:56 am

I'm not sure where I read that either, it was a long time ago haha. I think it had something to do with the sand being too wet. I know eco earth needs changed out, but what about sand? How often do you have to replace it?

Crabber85 · Post by **Crabber85** » Tue Dec 10, 2013 4:44 am

@Kirrie, it's the same for both substrates you want to change out at least eighty percent every six months for enclosures under thirty gallons and once every twelve to eighteen months for large enclosures.I'm currently using a 129 gallon aquarium and I only do substrate changes once a year or so, though I have let it go a full eighteen months and still had no problems.

Kirrie · Post by **Kirrie** » Tue Dec 10, 2013 5:47 am

Hmm definitely something to think about then! I like the eco earth that I have now, but my crabs drag it everywhere with them. Sometimes they dig holes right next to their water dishes so half of it ends up in the water and soaks it all up.I wonder what a mixture of eco earth and sand would look like. I know that the eco earth helps to keep some of the humidity in the tank, is sand any more or less effective?Sorry Im asking so many questions! I just want to make sure I get what is best for my crabs. I believe I have the basics for them in my 10 gallon now, but I really want to do better than that, like I do for my fish tanks

Geranium · Post by **Geranium** » Tue Dec 10, 2013 7:45 am

I like the mixture because the EE does seem to help with the humidity quite a bit. Mine ended up half and half but most I have read or seen photos of have a larger proportion of sand. I had one of the tanks in thirds, 1/3 sand, 1/3 EE, 1/3 mix. They all preferred to molt in the sand or the mix. They would dig in the EE and create channels along the walls but the windows that several of the crabs gave me when they were under, were all in the sand. The last of the mega number of photos in the link at the bottom of my signature line are of the new 55 gallon tank so you can see the mix if it helps.

Kirrie · Post by **Kirrie** » Tue Dec 10, 2013 8:14 am

That does help! I like the way it looks, I think I may just do that. Your crabs are adorable, by the way

I have to work on getting some more pictures of mine.

Crabber85 · Post by **Crabber85** » Tue Dec 10, 2013 8:37 am

@Kirrie, No problem answering questions is what we are here for. I have done the mix of ee and play sand in the past and while the ee did help retain more moisture in the substrate is was quite an insignificant increase compared with the cost of one brick of ee at my local pet store so I just opted to go with all play sand and I have not had an issue with it as of yet.The thing you have to remember about ee is its not a naturally occurring substrate like sand so hermitcrabs will react to it as if its a foreign substance so some will like it while others will not.I buy the Quick Crete brand play sand from Home Depot because it is a smaller grain which gives a much softer feel and has a pleasant smell almost like fresh baked cereal so I know the quality of the product is very high and like I said earlier I have not had a problem with it.