need advise

[fish4jun]

I HAVE 90G, GOT MY NEW 210G CAN I USE MY OLD SAND IN MY NEW 210G TANK. THE SAND IN 90G IS ONE YEAR OLD. THANK YOU.

[supertech3]

Yes, you will be adding many helpful things, better tan adding the live stuff in the ready made bags

[bertoni]

That's likely fine. If the sandbed in the 90g was clean and didn't have any problems, you should be able to reuse the sand. I've done that a few times when moving tanks.

[Randy Holmes-Farley]

If any of the sand is black or especially sulfur smelling, don't use it. Also, you cannot store it long in a bucket before it becomes anaerobic and produces potentially toxic hydrogen sulfide. A few hours is likely OK, but not 2 days.