Upgrading tanks, how much rock to keep?

[malfist]

Hey guys,

I've bought myself a christmas present of a 100g tank that I plan on replacing my current 65g tank. My 65g tank is about 5 years old now, if you count it's first year as a 29g biocube. Everything is in good shape and corals are growing. I currently have a 1.5" sandbed in this tank and a ton or rockwork that's rather ugly (it's a huge wall).

I don't plan on using a sand bed in the new aquarium, at least not at the beginning, only if things start going badly. In anticipation of this, I've added ceramic media to an empty chamber in my reactor to help build up an appendix of sorts.

Since my rock work is kinda ugly, I've created a new rock structure following BRS's HNSA video and it looks much better. However, I don't want to lose the biodiversity I've built up on my current live rock. How much rock do you guys think I should transfer over to the new tank to keep everything happy and not risk a cycle/dinos?

 

[ying yang]

Imo depends how big and how much room your new rock structure you made takes up.
But I see alot say if use all dry rock on a new tank then at least throw in a couple kgs of live rock for the bio diversity and let tje live rock seed the dry rock,so at least few kgs I would say but depends how much space you have left and how much of your old rock you want.so your choice.

But me personally of I had 5 year old rock and lots diversity I would want to keep as much as possible or at least half,but my decision would be made before I started making a new rock structure out of dry rock and plan it from there.
As you mentioning cycle/ dinos,I read alot more suffer bad algae outbreaks with dry rock rather than mature live rock and read when nutrients bottom out at 0 then gives dinos the upper hand as can compete better than other algae and the likes so of that's a concern then as much possible old live rock the better.
But I would also be thinking how many fish am I transferring over from old tank also as higher the bio load then older mature rock would handle it better but some start with quite a few fish and dry rock and bottle of bacteria and dont have problem,but most suggest stocking slowly on that scenario, so a few factors that will affect your decision but I can see most people recommending keep and use as much old mature live rock as possible for most smooth tank upgrade as possible ^_^

 

[Lineatus]

Depends on your bioload. If it’s high, than as much is you can, if not you can be rather lenient. You could try transfer as much as possible to your sump if you have space. Then just remove it after a couple of months when your dry rocks are seeded.

 

[malfist]

I was kinda thinking along those lines, I don't have a heavily stocked tank and have to dose nitrates and phosphates already to keep them above zero.

I made three big structures that will fill the entire aquarium, but I plan to leave at least one out to begin with, and filling it's vacant space with the old mature rock for a month or two. Just really trying to decide if it should be one structure I leave out, or two. Some rocks have to move over, my anemone and clam rocks for sure, and the rocks that my green singulara and zoa's have overtaken

 

[ying yang]

I was kinda thinking along those lines, I don't have a heavily stocked tank and have to dose nitrates and phosphates already to keep them above zero.

I made three big structures that will fill the entire aquarium, but I plan to leave at least one out to begin with, and filling it's vacant space with the old mature rock for a month or two. Just really trying to decide if it should be one structure I leave out, or two. Some rocks have to move over, my anemone and clam rocks for sure, and the rocks that my green singulara and zoa's have overtaken

Sounds like good plan