If you're doing dwarf puffers the 6 gallon eclipse tank would be ok for two of them. But of course, don't let me stop you from getting a new tank
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. I actually have 2 dwarf puffers in an eclipse 6 right now.
How long has your tank been without fish? If the tank goes too long without (don't know how long???) there will be no ammonia (fish poop) in the water to feed the good bacteria on your bio-wheel. What this means is that when you start adding fish again you'll go through another cycle. Somebody please confirm that this is correct or correct me if i'm wrong!!
It's really better for the fish to do a fishless cycle, there's a pinned topic in the beginners forum about this.
However if you want to cycle with fish supposedly zebra danios are some of the best.
I would just empty all of the water and start with just fresh water (make sure you dechlorinate it!!!).
You'll really need to get those test kits before you'll be able to tell when your tank is done cycling, simply just waiting a month is not enough. Don't get the puffers until you know for sure that your nitrites and ammonia are down to 0.
I'm sooo glad to hear that you are actively doing research and are truly interested in making the fish happy and such! Fish keeping takes patience but it is so rewarding, like when you feed your dwarf puffers and you can almost see them smiling back at you
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Here's two good links on dwarf puffers:
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http
/www.rr.iij4u.or.jp/~kohda/en/en-dwarfpuffer.htm
SOMEBODY PLEASE CORRECT ME IF I'VE SAID ANYTHING WRONG. I don't want to give him bad advice
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. Feel special tdwag57, this is the first message where I've acually given somebody else advice
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Edit: don't know why the first link won't work. It's "www.dwarpuffers.com"