Displacing water

[crisscross]

Im going to start a new run soon. The new run will be in a relatively tall Tupperware like container. The reservoir is large therefore, until the plants develop any roots, I want to displace the water by putting something heavy and small in my reservoir. What can I use that will not leech anything into the water. I was thinking a cinder block or something but I don't know if that's a good idea or not.

Has anyone else used a sense material to safely displace water before?

Thank you!

 

[Maj.Cottonmouth]

You could use hydroton but remember that water follows the rules of gravity and will level itself. In other words it doesn't matter how tall your res is, the water level will not be higher in it than it is in your buckets unless you are pumping water into it faster than it can drain.

 

[wilbur]

seems to me cinder block could contain leachable ingredients.

perhaps something made of stainless steel or cusilman bronze (that's an amalgam of copper, silicon and manganese ... used for hot water cylinders where the water is heavily alkaline/corrosive.) or lead encased in an inert plastic.

cheers!

 

[mcfly420]

wet sand in plastic bottle?

 

[exploziv]

tap water in plastic bottle?? the cheapest and simplest way to do it.

 

[Friend]

yeah i was gonna say a gallon jug filled with water will do the trick.

 

[crisscross]

container of sand is a+ answer. The bottles of water will float and potentially mess with my bubbles

 

[gtgio]

Big jugs of water. You can always freeze them to cool the res, too.

edit: I bet you could figure out some way to secure the bottles to the bottom via a suction cup or something. Sand works too.