tank upgrade? about cycle.

it will cycle and the disturbance of the sandbed will likely create/release some nutrients. i would just monitor and have water change ready to go, should be fine

 

When I did this I had no cycle. But honestly there is no point in using the same water, your best off just using all new.

 

I've moved into progressively larger tanks 3 or 4 times now, and it's always a fire drill. You will be up all night, likely until 8am the next morning, and inevitably much of the water will look so disgusting you won't want to transfer ALL of the water, make sure to have plenty of new on hand, I've never had any indication of a new nitrogen cycle occuring during these switches, they all seem to go very easy. I would certainly salvage a good portion of the water you have now because of temp and oxygenation issues, but the bottom 30% of it you want to waste for sure, fill the rest of the tank with new and get ready for a marathon!

cya,
Andy

 

I'd use at least some of the existing water. That's the water your livestock is used to. There's got to be a reason we don't do 100% water changes.

 

FWIW some people actually do get pretty close to 100% with no adverse effects.

 

yeah the water really holds no bacteria or anything, that is all in your rock and sand. I think the biggest reason we dont do 100% water changes is out of convenience and expense. I found the water that you end up with just from transfering the sand is plenty.

 

I would use the water, why wouldn't you? Its a waste, not to. The reason we don't do 100% water changes is for stability.

 

we add chemicals use reactors and stuff to keep water stable, doing water changes replenishes what gets evaporated or used that we do not dose for. there is no reason not to do 100% water changes other then time and money. unless you dose for everything constantly, then you never need to do water changes. The 15% thing is a standard we use to replenish what we use/lose over a period of time.
Anyway all I was saying is by saving your current water your not saving any kind of beneficial bacteria that would save you from a cycle. That is all in your rock and sand.

 

In the words of Bob aka bullet....." Not changing your water is like not flushing your toilet "

 

My 2 cents. I upgraded and I used 100% all old water with my old rock, but new sand. 0 cycle and everything went smooth and great. Just sharing my experience.

 

+1 on the water not holding the nitrifying bacteria, but thinking that live stock will respond well to possibly huge changes in concentrations of discrete elements of sea water is naive. Perhaps it's been done, but it's not qualitative to say that its been done without problems, who knows how much offense animals take to water changes, especially corals. I would argue that for that reason alone, slow and steady is the way to go, do what you have to in order to move things over, but I think that 100% water change is excessive, and not only for economic reasons.

 

+1 Andy