wrong sand grade for DSB

[Alentino]

4 months back when i started to construct a DSB in my sump, i filled it up with 3 inches of 1.0-2.0mm of medium grade sand. my original intention was to fill it up till 6 inches, but i have run out of sand. so i asked my father to help me buy more sand and top it up till 6 inches while i had to be away from home for quite some time.

when i finally returned i discovered to my horror that my father had bought the wrong sand grade for top up, he bought 2.0-4.0mm of coarse grade sand and he had already fill them on top of the medium grade sand. so it's a bottom layer of medium sand and coarse sand on top, each layer 3 inches. I'm not sure whether this mix will still be a functional DSB. What should i do to improve things? Please advise

[Terryz_]

4mm sound like coral chip liao...

[Alentino]

actually i don't know how to tell sand grades, i only know its about that size from this website http://www.wetwebmedia.com/deepsandbeds.htm

i could be wrong about the grain size but it does look like what it's shown in the pics

[Alentino]

anyway, should i remove the coarser sand on top?

and what would be the ideal sand grade for DSB?

[Alentino]

thanks for the replies,

hi benz, only the 1.0-2.0mm and the 2.0-4.0mm is available in my lfs and those folks also can't tell me what grade are those. i just told them i one their finest available sand. We are in Malaysia by the way

the DSB is located in my sump which has nothing in it, no livestock/LR whatever. sump dimension is 2.5 x 1 feet i think.....

i think i wanna replace the coarse grade with the grade 1 sand