Double decker 20 gallon tanks

[CRAIGARRR]

I have 4 hermit crabs and I want to give them more room.I was thinking of taking another 20 gallon tank and putting it on top of the existing one. With a branch leading up to the second floor. If I put another tank on the access I have to lower tank will be limited so thinking of setting it up for living quarters on the bottom only , a few logs, a couple of huts some branches to climb on and deep substrate of sand and coconut fiber to dig and molt and just chill out. The top would be for feeding and water and salt water/fresh water sauna. a 4 inch layer of just coconut substrate to walk on with a few limbs to crawl on and even a limb that would lead to the top screen because they do enjoy climbing around on the screen hanging upside down. Has anyone tried this? I can't find any pictures for ideas. The bottom of the aquarium is glass obviously and I need a way to pop a hole into it for a tree limb to go thru so they can climb up to second level. I suppose I need a glass cutter and score the glass and tap it and hope it breaks in the scored lines? I dunno, have never used a glass cutter when the glass was surrounded by something, just used it to cut glass to make it shorter and narrower. Will a glass cutter make a square in the glass with 4 scored lines or will it just shatter the bottom of the aquarium? Was thinking of just smashing the bottom out and replacing it with some thick plexy glass that I can use a jigsaw to cut out a hole. But that costs more. I know there are hole saws for glass but the hole I need to make is 4-5 inches in diameter and I imagine the cost is ridiculous and not spending money on something that is a one time thing. Any suggestions?

[wodesorel]

All I know that is that removing a side from an existing tank is extremely dangerous. That silicon seal doesn't let go easily and the glass will shatter and chip. I've tried to alter spares and already cracked tanks and have been cut pretty good. I have never tried to cut it, but so long as it's not tempered glass (and a 20 gallon shouldn't be unless it's ancient) it can be cut and drilled. Fish people do it all the time to run plumbing and filtration, but it's not without it's risks and you can end up with a shattered pane of glass. Just google "drilling an aquarium" for videos and information. I'm pretty sure it takes a specialized hole cutter though, so unless you already have the tools it would probably be a lot cheaper to just buy a new bigger setup either used through classifieds or new on sale, and sell your existing tank to make up the difference. Keep in mind that for hermits the floor space is the important part since molting is the most dangerous time for them!

[aussieJJDude]

Going on what Wod was saying; one can use a hand held drill (with a diamond drill bit); a steady hand and a tonne of patience! If serious about this; try resourcing tutorials about this to develop a strong understanding.

[Crabinski]

Some folks on the forum have gone double-decker using an Eco-Terra terrarium as the top piece. I gather that it's much, much easier (and safer) to remove the bottom glass from an Eco-Terra than from an aquarium tank. You'll find some threads by searching the Crabitat section for Eco-Terra. The downside with any double-decker will be readily accessing the lower level for daily maintenance (changing food bowls, water in the pools, etc.), especially if the tanks are sitting on an aquarium stand or dresser.

If you're looking for more climbing room, keep an eye out for a taller tank on craigslist or the periodic $1-per-gallon sales at Petco/PetSmart: a 29g has the same footprint as a 20L but is 6" taller -- a mere 6" may not sound like much but it'll easily handle second levels, hanging vines, shell shop hammocks, raised moss pits, climbing branches, etc., without sacrificing substrate depth.

[CRAIGARRR]

Thanks for your replies.. I have decided I don't want to mess with getting cut. I am going to cover both sides with duck tape and smash out the bottom and just replace the bottom with a piece of 1/4 plywood and cut the 5 inch square into it, rather than messing with glass.Put my crabs in the new tank temp. with half inch substrate and some huts. Not a great time to do it because here in New England it got down to 45 degrees last night. Stayed 68 inside. Covered it with blankets and this morning it was down to 66 in here so fired up quartz heater and warmed it up. They are all in one hut (3) keeping warm together. Gave them a bath and did not want to put them back in the dirty but heated aquarium. Is only for less than a day hope they don't get too stressed out.But it in the long run it is for the better, they will have double the space that they had.Cleaning the heated aquarium today. Only problem I forsee is if I try to smash out the glass and the side panels are ontop of the bottom, it might hurt the side panes as well.. Oh well will see what happens when I start smashing the bottom out with eye protection and gloves.Will take even one more precaution and put it in a big plastic garbage bag before smashing.. Wish me luck!

[MicroMary]

I will add an additional second deck to my 30g by making my own own acrylic aquarium to sit on top of my glass aquarium. Acrylic is sold at hardware stores and is much easier to work with and remove for cleaning purposes. I already have the plans worked out, you could always consider this since plywood can be tricky with the humidity and water.

[soilentgringa]

Just wanted to chime in here.

The OP is about 9 months old, so I don't expect the poster to respond.