Upgrading: Some Tank Changing Questions

[kenettson1]

Well, I'm finally upgrading my 75g to a 5x3x2 acrylic.

My questions:
1. Should I use as much water from my 75g and plumbed-in 100g stock tank as possible in the new tank?
2. If so, and I top off the rest with new water will the tank go through a significant enough cycle to kill SPS/fish/anything?
3. Do you think 2x250 MH will be enough to light this tank?
4. Completely new sand bed or use some new and some old?
5. Will 2x6000 Tunze Streams be enough flow?

Thanks in advance for your help. I go to pick up the tank tomorrow. It should be a sweet setup with a plumbed in frag tank, nice equip, THE WORKS!

 

[orchidsnfish]

Using some new water is not going to make the tank cycle. As long as the live rock is in good shape you should be ok. I would use new sand and a few handfuls of old or wash the old sand heavily at least before using it.

Angela

 

[mflamb]

I would use about half of your current water, all of your current rock, and then use the rest of your current water to rinse your current sand and use all of the current sand plus whatever you new sand you need to reach your desired depth of sandbed. Two 250MH should be sufficient. You may want to supplement with t5 actinic for color.

 

[stlouisguy]

What are you going to be keeping in there? If sps then you need more flow than 2 6000's, add a few 6100's or 6200's you need that water really flowing!!

 

[kenettson1]

Thanks for the info. So none of you think by using about 70% new water that I will have any cycle? I have about 10 sps colonies\frags that Ive had for a while that I dont want to risk.

My plan (tell me if Im wrong)

1. Rinse new sand in RO and put about 2-3 inches in new tank.
2. Mix new water and fill tank to about 70% full.
3. Siphon enough old water off to fill frag tank and hold all livestock there while filling the main tank with the remaining water from the old system.
4. Turn on pumps - wait for problems

 

[SFreefer]

I'm in a similar situation. Going from 55 to 220 soon. Any ideas are great. What about needing more rock to fill new tank out? Sorry if this is a hijack. Not meant to be.

 

[ruiny]

I have done several upgrades over the years and have always used as much water from the old system as possible. For the new water just make sure the temp and salinity are correct. And by reusing your rock you will be moving the bio filter instead of growing a new one which is your cycle. Like stated as long as there is not a lot of die off and no increased bio load than you should not get a new cycle.
If possible don't add a lot of new live rock all at the same time.