can i put 2 55 gallons on a 180 gallon stand temporarily?

so one 55 wouldnt work in the middle? i was kind of relying on it to be able to while my grandpa fixed my current stand.

OP stated 2 55 gal. tanks on the stand. You could beef up the stand to support the 55 where needed. Only a temporary set up.
 
Do you have fish that need a 4 foot tank? I might be inclined to use a bunch of small tanks(or clear plastic storage containers) oriented sideways for temporary housing. And of course doing lots of water changes to make up for the lack of water volume.
 
3/4" plywood or better would be a better bet for a temporary fix. would help to spread the load with the extra layer. foam wouldn't help much if at all.
 
If you want to put the tank or tanks on the floor....put them on the floor. It won't hurt anything.
 
If you want to use the stand you have for 2 tanks all you need to do is build a support of the middle section. 2x3 from the homedepot, you can have them cut them to the size you need. the top piece should be full length, then minus out the with of the top piece so your support arms rest flat on the floor. screw it all together when you get home, and put your tanks on it. A very simple project. or you can place them on the floor, if they are going on carpet I recommend a piece of plywood an inch wider then the tanks, carpet could put extra stress on the bottom glass.
 
i got some 3/4in plywood. its 4x8. how would you place the tanks on this? this is upstairs by the way. i was thinking one on each side instead of side by side like this l l instead of --
 
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