Starting up old tank with gravel sill in it

[Jim peters]

I have an old tank 75 gallons with gravel still in it it's been sitting for a few years what can I do to restart that tank and still use that gravel and the gravel is hard as a rock and it was a planted tank and had some clay mixed with it

Edited January 19, 2022 by Jim peters

[Levi_Aquatics]

I would fill the aquarium and then gravel vac. I have done that a few times and never had any issues.

[KaitieG]

If it's been sitting,  you'll want to make sure everything is still sealed well, too.  Sometimes silicone can dry out.  I don't know how clean/dirty any of it is...if it looks good still, just do what @Levi_Aquatics said, but I'd do it somewhere you don't mind getting wet to check for leaks before setting it up in, say, a carpeted living room.  If you have to do a bunch of cleaning (mineral deposits, etc.), I'd move the gravel to a couple buckets, clean and leak test the empty tank, rinse the gravel, and then move everything where you want it to end up.  

[lefty o]

id put the gravel in a 5 gallon bucket, and flush that out real well. place the empty tank somewhere safe, and give it a few day leak test.

[Tanked]

You have to clean the tank anyway, so as the others have suggested, go ahead and leak test it.  Depending on how carefully you stored it, an aggressive gravel washing may be in order. I have found many foreign objects buried in old aquarium substrate that the gravel vac missed.