Getting closer

[Ab129]

So I now have added dry sand to my tank with my dry rock formations in place.
Was shooting for a 1 1/2 -2 inch deep sand bed and ordered 60 pounds of sand for my 75 gal tank. Seems as though I have more sand than I wanted though.
Now I have 2 rock islands that are on egg crate supported by short pvc stands so the bottom of the rock is maybe 1 1/4 inches off the bottom of the tank.
Should I push the sand under the rock to fill in the gap underneath or just let that happen naturally when I fill the tank?
Also, when there is water in there will the level of the sand come down a bit or not really?
I would prefer to not have to remove sand once I have the tank filled.
Thanks for any advice!

 

[mcgyvr]

Did you mean you have "less sand than you wanted"?

I'm not understanding why you need to push sand under the rocks to fill a gap that are 1-1/4" off the bottom when your sand is higher than that..

The sand shouldn't settle much if any when the tank is filled..

 

[Ab129]

No. It seems I have more sand than I wanted. It's 3+ inches in spots, but since I added it after the rocks were in, it is now just surrounding the rock islands. The space underneath the rocks is empty. After I fill the tank I assume the sand will naturally fill in the space below the rocks but if it's still too much sand I would rather take some out now before I add water.
I don't know, I am probably just overthinking this (I tend to do that).

 

[mcgyvr]

Personally...The sand should be placed first and then the rocks/structures should be "sunk" (wiggled or whatever) down into it prior to filling the tank..
Do not rely on the sand naturally flowing where it needs to go after filling.. that won't happen properly..

So I envision you sinking those PVC tubes down into the sand and the inside of those tubes should be full of sand now..

Sand can actually be eroded out away from under the rocks (if they aren't on the bottom) over time/from critters moving it,etc.. and that may cause the rocks to be unstable and topple over so the rocks or pipe structure should be in physical contact with the bottom glass..

But this isn't rocket science.. I'm sure you can use your brain and do whats right..

 

[Ab129]

What's the downside to me just pushing the sand under as best I can.
I really don't want to take those rocks out unles it is absolutely necessary.

 

[mcgyvr]

Just push the sand down there already
Its fine..

 

[Ab129]

That is just what I wanted to hear lol!
Thanks!

 

[top shelf]

By all means correct me if I'm wrong but wouldn't you wanna place the rocks then dump the sand in? If sand is put in first then rocks "wiggled" down into it doesn't that present the exact issue you mentioned of erosion and critters digging making the structure unstable? If rocks are placed first then sand dumped around them then they are already on the bottom and nothing can dig under them and the sand can't be washed out from underneath.

 

[mcgyvr]

By all means correct me if I'm wrong but wouldn't you wanna place the rocks then dump the sand in? If sand is put in first then rocks "wiggled" down into it doesn't that present the exact issue you mentioned of erosion and critters digging making the structure unstable? If rocks are placed first then sand dumped around them then they are already on the bottom and nothing can dig under them and the sand can't be washed out from underneath.

yes you are correct..
I personally find putting the rocks on bare glass kind of like nails on a chalkboard/scary...so I choose to apply sand first then wiggle rocks all the way down into it..

But again.. really doesn't matter.. Not rocket science here.. just don't let the rocks float as the sand can/will move out from under them..

 

[sde1500]

I too prefer the rock wiggle method.