Question on upgrade to a larger tank.

I currently have a 97ltr Marine Nano (Resun DMS 500) and have just purchased a new 175ltr tank; it will arrive towards the end of the week.
Live rock for the new tank will comprise of half new and the other half coming from my existing system.
Should I first cycle the new tank with the new live rock (1/2 of what is required for setup) before transferring my existing live rock, fish and corals?
I have read different articles, some suggest the above method, others suggest immediate setup of new tank with a mixture of salt water from old tank and new, as well as moving the live rock, corals, and livestock, with no period of cycling.
I will not be transferring any of the existing sand, or filter media into the new tank. Which method is likely to provide the best results?

 

This is just my opinion, but it seems as though you will have a short cycle with the new rock, sand and filter media. I would seed the new tank with rock, sand and water from the existing tank and let it cycle for awhile first. There's no need to rush into things and be fighting a cycle. Lets see what someone else with a little more experience thinks.

 

Thanks for the response.

But, if i put rock from old tank into new, along with water i would also have to move livestock over as there would be no rock and water remaining in old tank. If that makes sence

 

I see your concern. When you put water from the old tank into the new tank, you would only put about 10-15% of the old water into the new tank. Sort of like using the old water from a water change. This leaves plenty of water in your old tank and gives some established water to your new tank. So that shouldn't be the issue. The only think I could see possible being a problem is when you get rid of 5% of your established live rock, it could hurt your biological filtration a bit, so You could go ahead and acclimate one or two of your hardiest fish into the new tank to even the load and start the new tank. The cycle is going to be shorter, but you still want to treat it like a new tank and stock it nice and slow.

 

someone please correct me if I'm wrong, but this seems pretty logical.

 

Current live stock is: 1 x Clown Fish and 1 x Yellow Tail Damsel, 2 x cleaner shrimps and 7 x red legged hermit crabs. Therefore i dont think the bio load would be too heavy.

 

That's definitely a small bioload. In that case, you probably could just transfer everything at once.

 

IMO Blue Falcon is right

with only that live stock to take into account, I would move all the water and rocks from the existing tank into the new one

the only concern would be if you added new live rock, some of the life would die off causing the cycle that you are worried about

if you used base rock/ dead rock - and a new sand base - you wont have this die off issue to worry about

mix up a new batch of salt water, up to about half of your new tank add the base rock and the new sand base
let it settle and mix for a week - with heater and Power head

then add your existing water, rock and fish to it

if you can take even longer about it, you can start filling your new tank with water saved from your old tank during weekly water changes - which again when time comes would reduce the amount of new / immature water that your livestock is expossed to

Steve

 

Thanks Steve and Falcon.

I have a plan now.....

I will setup the new tank with its new live rock and leave it to settle for about 2 weeks, with powerhead and heater running.

I'll then add water from my weekly water changes out of my old tank for another 2 weeks (2 lots of water, about 25ltr per change).

Once this is complete i'll transfer all livestock and corals to the new tank.

Hopefilly this way i can avoid disaster