Sand Particle Size vs Flow vs Pistol Shrimp

[NeonRabbit221B]

My Evo 13.5 has an interesting problem where my pump upgrade to an MJ1200 drastically improved my growth and filtration but has a tendency to allow sand to easily pile up. It didn't bother me at first but after fragging some coral and losing them all to the shifting sand bed I was thinking about replacing the sand bed. My pistol shrimp also tends to fairly easily burrow and move massive piles of sand around which nearly led to a collapse.

My plan is to replace the fine sand bed with a course sand bed and maybe place some egg crate in the bottom to prevent the sand from shifting around. I have no clue the exact type I got originally but I think it was Special Grade of Fiji Pink. What sand would you all recommend as a middle ground between being heavy enough in a high flow tank but light enough where a pistol shrimp can continue to burrow but not completely uplift the entire sandbed? Should I replace it all or just replace half?

 

[Krully]

I'm not sure about the grain size but I believe I started with really fine live sand (like probably 1mm, sorry I'm european) and then added bigger sand because of the same issues. I just mixed the two together and it's doing okay, the mix prevents the fine sand from moving too much and there's more stability overall for the shrimp's burrow so he doesn't have to move everything again ten times a day.

 

[NeonRabbit221B]

I'm not sure about the grain size but I believe I started with really fine live sand (like probably 1mm, sorry I'm european) and then added bigger sand because of the same issues. I just mixed the two together and it's doing okay, the mix prevents the fine sand from moving too much and there's more stability overall for the shrimp's burrow so he doesn't have to move everything again ten times a day.

That is very good to hear. What was your method on this? Did you pull all rock/inverts/fish and just scoop it out or siphon a large amount of the sand out and put the new on top?

 

[Krully]

I did scoop some of the fine sand right from the tank but because I knew it was vacuumed thoroughly twice a month and that I had a shrimp moving it a lot all the time, I wouldn't risk it on a sand bed that doesn't move because you could nuke the tank (but that doesn't seem to be your case? be careful anyway). Then I rinsed my new sand a lot and just added it with a glass lowering it gently in the tank and dropping the sand slowly, water still ended up a bit cloudy for two hours but no issue afterwards. I let my critters and next vacuumings do the mixing.