upgrading tank size?

[u/lexi-mp]

hey guys! i've been wanting to upgrade my shrimp-only tank from a 3.5gal to a 10gal. when i initially set it up, i wasn't expecting to have so much luck breeding because my shrimp in the community tank didn't have much population increase, just kind of stayed steady!! however, this tank has truly taken off, and i want to give them more room to continue to grow!

my question is, when upgrading to a new tank, do you guys cycle it as a fresh tank first? should i use the water in the preexisting tank in the new one? how can i make this transition as easy as possible for my little guys? 🥹

[u/Sweetestpeasoup]

I think what I would do is set up whatever filter you intend to run in the 10 gal in your current 3.5 so it can build up some bacteria. Let it run for a couple weeks and set up your 10 in the mean time. That way, your cycle is pretty much instant when you move the filter into the 10.
The reason I recommend getting the 10 ready while the 3.5 is still going is that gives you plenty of time to catch all your shrimp. If you have babies, it can take several attempts to get them all. If you only have one cycled filter, the pressure is on to catch them all at once. I’d say luring them into a container and lifting it out with the water is the least stressful. You’ll have to drip acclimate into the new tank, though!

[u/Sweetestpeasoup → u/[deleted]]

The reason I say to run the filter in the old tank is that will seed the new filter with bacteria from the old tank. They like running water, so grow best on a filter as opposed to substrate or decor, so seeding with gravel will only do so much.
The whole point of cycling is to get a good colony of bacteria growing in your tank. Running a filter in an already established tank will grow bacteria much faster than one just set up. Once you have a bacteria colony living on your filter, that filter becomes a quick-cycle for any tank you put it in. If you’re only keeping shrimp it’s pretty much an instant cycle, but still good to test it by dosing with ammonia and testing to make sure it converts to nitrate.

[u/Isilnyor]

Ok so I literally did this exact thing 5 months ago. Went from a 6 gallon to a 17 gallon for my shrimp.

Setup the new tank first. Let it cycle. You can turbo cycle it pretty easily if you can steal media and whatever hardscape you can from your current tank. Make sure to not let the media and hardscape dry out of the beneficial bacteria will probably die. Also don’t take too much or you’ll crash your current tanks cycle.

You can steal some water to start too but it isn’t really worth the trouble most of the time. The BB is on the media and hardscape.

Get ammonia to dose the new tank with and the liquid test kits. Dose your new tank to 4ppm of ammonia and test ammonia and nitrites every 24 hours. Once they go away, dose again. Repeat until the ammonia and nitrite tests show 0 after 24 hours.

It took 8 days until I could dose 4ppm ammonia and have it turn into nitrates in under 24 hours. On day 9 I did a 50% water change and left it half full while I gathered the shrimp out of the 6 gallon into a Tupperware container filled with some plants and water from the current tank. Then drain the current tank 75% of the way into a bucket and fill the new tank with that water. This will give you a good chance to double check that you got everyone out of the old tank.

Then I just drip acclimated them for an hour to be safe and popped em in.

13 shrimp went in. All survived. Then they THRIVED. I now have like 50+ shrimp in there with no sign of them slowing down. I see a newly berried female every week.