Upgrading from two small tanks to one big tank

senorsancho · Mar 23, 2021

So right now I have a 25g and a 20g reef tank setup that are both packed with coral and fish, but I am looking to upgrade to an 80g tank. I am wondering what would be the best approach to upgrade both these tanks to put all the livestock, live rock, and water from these tanks into the new one.

I want to place the 80g in the same spot where the 20g is, so would it be best just to transfer over everything from that 20g into the 80g with new sand and all the amount of water i would need to fill up the 80g and sump? Or should I go ahead and just combine both of the tanks using all the live rock, water, and livestock and then I can just add whatever more water is needed and maybe a bottle of bacteria to just help with the new substrate and water and I should be okay?

Also, if somebody could recommend what size return pump and what size sump I should use on the 80g, that would be great too!

laverda · Mar 23, 2021

I would get the 80 set up with sand and some water up to temp. Then add everything from the other tanks. Rock work first. Then water and fish. Just a cup full of sand from each tank, if you have critters in the old sand.
For return pump it depends on how much flow you want and if you plan to feed other equipment off it. How much flow your overflow and drains can handle is also critical. Usually you want 5-10 Times tank volume flow through the sump. So you want a pump capable of flowing 400-800 GPH after allowing for head height including restrictions of your plumbing.
I personally would get the largest sump pratical that has the features you want. Things you might want are filter socks, fleece roller, refugium, room for a skimmer and or reactors, heater holders, probe holders, built in or separate ATO container. If it is going inside the stand, Keep in mind any other equipment you will want there. Having electrical equipment separated from water sources is always a good idea.

senorsancho · Mar 23, 2021

laverda said:
I would get the 80 set up with sand and some water up to temp. Then add everything from the other tanks. Rock work first. Then water and fish. Just a cup full of sand from each tank, if you have critters in the old sand.
For return pump it depends on how much flow you want and if you plan to feed other equipment off it. How much flow your overflow and drains can handle is also critical. Usually you want 5-10 Times tank volume flow through the sump. So you want a pump capable of flowing 400-800 GPH after allowing for head height including restrictions of your plumbing.
I personally would get the largest sump pratical that has the features you want. Things you might want are filter socks, fleece roller, refugium, room for a skimmer and or reactors, heater holders, probe holders, built in or separate ATO container. If it is going inside the stand, Keep in mind any other equipment you will want there. Having electrical equipment separated from water sources is always a good idea.

Ohh okay awesome yeah I was planning I would empty the 20g, take out the rock and lay them in a tub, then get the fish out, and move the tank out of the way and get the new one in there and then yeah I would probably make two big brute tubs of saltwater and heated ready to fill up the new tank and then just put all the new stuff in and then also break down the other tank and do the same once there's a reasonable amount of water in there and then acclimate the fish and get them all in there. Alright that sounds good then, i'll probably just make sure to have some kind of filter or something going wherever I put my livestock.

I decided on an 800gph return pump I figured it should be good once I have plumbing setup and then it'll go down and still get me that 2-5x turnover. My tank I would be getting is a 48x24x16 80g frag style tank and then I am getting an eshopps prodigy drilled onto it for overflow, I was wondering whether to go with the M or L but I think I will go with the L size of it. Would a 29g work for a skimmer? All I really wanted was just to be able to throw a good sized skimmer in there like a bubble magus curve 7, then just 2 heaters, and then a filter sock, would be great if I could have a little area to act as a frag tank but I would be okay without it I could just use an old tank as a little separate frag tank in another room lol. Maybe 29g should work, or would you suggest a 40g? I am trying to diy the sump and find a decently priced baffle kit somewhere online.

laverda · Mar 23, 2021

I would not even bother for just a 29 gallon sump, as it doesn't give any room. 40 would be better.
I once did a sump by just using pieces of acrylic that were 1.5" shorter than the with of the tank. I heald them where I wanted and used sand and rock to hold in place. The water flows back and forth instead of over and under. It was a much better use of space. No micro bubbles at all. It could easily be changed if I wanted to. Makes the whole sump the top off compartment, not a tiny little area. That helps a lot if you don't have an ATO.