Sand? Plants? Heating?

[Justthreehermitcrabs]

Hello everyone!
I have a 55 gallon aquarium housing 3 large hermit crabs. I’ve had the setup for a little over a year now and I’m planning on cleaning the tank very soon.
Every year I usually refresh my knowledge on their care but I have found many different opinions/unanswered questions! As my crabs are growing and I get more experience, I want to provide them with the best environment possible.
So my first question is about substrate! Right now I am using a mix of about 2/3 all purpose sand and 1/3 eco earth. The all purpose sand in the tank is very rocky (has pieces of gravel) and is a darker color which I don’t like all that much. It also makes the tank look dry! This year I want to use play sand (the brand from Lowe’s) but I have heard many different opinions on it. Is play sand the best to use? If so, what brand? Also, would it be a good idea to mix crushed oyster shells into the substrate as an extra calcium source?
I also want to make it a different ratio. I plan on using 1 cup eco earth to every 5 cups sand, does this also sound good? My final question on substrate is, should I stick with sandcastle consistency substrate? Is that still recommend?
So now on to plants! I want to add a couple live options to the tank. I’ve heard that spider plants and chia sprouts are safe, would they do well in the warm and humid environment? Also, would anyone recommend any other plants like pothos or fern (if so, please tell me the type!)
Finally, heating! Right now my crabs have a Zilla UTH heater on the side of their tank but I want to upgrade it. What size would you recommend for a 55 gallon tank?
Other upgrades to the tank will include 10 inches of substrate (right now they have 7-8), a worm casting digging area, more climbing options, water dishes that are easier to clean, some river rocks added by the entrance of the water dishes, new and improved water dish ramps, and a duct taped/plastic wrapped lid!
I asked a ton of questions so even if you could just answer one that would be AMAZING! Thank you for reading, any help is appreciated

[Hermiesguardian]

Hello everyone!
I have a 55 gallon aquarium housing 3 large hermit crabs. I’ve had the setup for a little over a year now and I’m planning on cleaning the tank very soon.
Every year I usually refresh my knowledge on their care but I have found many different opinions/unanswered questions! As my crabs are growing and I get more experience, I want to provide them with the best environment possible.
So my first question is about substrate! Right now I am using a mix of about 2/3 all purpose sand and 1/3 eco earth. The all purpose sand in the tank is very rocky (has pieces of gravel) and is a darker color which I don’t like all that much. It also makes the tank look dry! This year I want to use play sand (the brand from Lowe’s) but I have heard many different opinions on it. Is play sand the best to use? If so, what brand? Also, would it be a good idea to mix crushed oyster shells into the substrate as an extra calcium source?
I also want to make it a different ratio. I plan on using 1 cup eco earth to every 5 cups sand, does this also sound good? My final question on substrate is, should I stick with sandcastle consistency substrate? Is that still recommend?
So now on to plants! I want to add a couple live options to the tank. I’ve heard that spider plants and chia sprouts are safe, would they do well in the warm and humid environment? Also, would anyone recommend any other plants like pothos or fern (if so, please tell me the type!)
Finally, heating! Right now my crabs have a Zilla UTH heater on the side of their tank but I want to upgrade it. What size would you recommend for a 55 gallon tank?
Other upgrades to the tank will include 10 inches of substrate (right now they have 7-8), a worm casting digging area, more climbing options, water dishes that are easier to clean, some river rocks added by the entrance of the water dishes, new and improved water dish ramps, and a duct taped/plastic wrapped lid!
I asked a ton of questions so even if you could just answer one that would be AMAZING! Thank you for reading, any help is appreciated

Sounds awesome! Great questions. Playsand is still recommended. Really any ratio you want but 5:1 sand:ee is the most common I think. Yes, sandcastle consistancy is of upmost importance. It has to hold its shape for their tunnels and caves. Make sure it's mixed with either dechlorinated fresh water or dechlor salt water. Prime to dechlorinate and Instant Ocean added for salt. Adding oyster shells to the substrate is fine. I would just say not too much so the substrate is not too "rough". But that's me. You should get a UTH that covers the entire back of the tank from the top of the substrate to top of tank. And one that can be insulated is best. That would not be one from the stores. You can get an Ultratherm from beanfarm.com or reptilebasics.com. An easy way to clean the pools is to double them up so the bottom one holds the shape in case there's a crab underneath. You only lift out the top one. Any live plant you put in they will eat or pick at. Which is fine as long as it's on the safe list.
Do you have a digital therm/hygrometer? They are much mor accurate than analog.
I think that covers your questions pretty much. I'm sure others will add their advice too. Post pics when you're done. We love pics.

[Justthreehermitcrabs]

Sounds awesome! Great questions. Playsand is still recommended. Really any ratio you want but 5:1 sand:ee is the most common I think. Yes, sandcastle consistancy is of upmost importance. It has to hold its shape for their tunnels and caves. Make sure it's mixed with either dechlorinated fresh water or dechlor salt water. Prime to dechlorinate and Instant Ocean added for salt. Adding oyster shells to the substrate is fine. I would just say not too much so the substrate is not too "rough". But that's me. You should get a UTH that covers the entire back of the tank from the top of the substrate to top of tank. And one that can be insulated is best. That would not be one from the stores. You can get an Ultratherm from beanfarm.com or reptilebasics.com. An easy way to clean the pools is to double them up so the bottom one holds the shape in case there's a crab underneath. You only lift out the top one. Any live plant you put in they will eat or pick at. Which is fine as long as it's on the safe list.
Do you have a digital therm/hygrometer? They are much mor accurate than analog.
I think that covers your questions pretty much. I'm sure others will add their advice too. Post pics when you're done. We love pics.

Thanks for the reply, all of that information is SO helpful! I forgot to add in the post but yes I will be switching from analog to digital (I just got a leopard gecko and realized how amazing digital thermometers/hygrometers are). I will post pictures once I finish the tank