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Water Changes in an Octopuses tank...

Jan 6, 2003
I was just wondering...I never knew exactly how you do water changes in an Octopuses aquarium. How do you do it EXACTLY??
Do you take the octopus and put it in a bowl or something or a spare tank for a few minutes, and then dump all the water out of the tank and refill of it again? It seems like a LONG LONG process considering...setting up the water all over again. Like...after taking all the water out from b4...in order to make a new batch of water for your octopus...you gotta do the R/O unit system first....then you gotta fill in the tank slowly by slowly...
Then you have to put in all the sea salt...and then you gotta keep testing and waiting to see if the sea salt is just right 1.026 or w/e. And then finally put the octopus back into the tank. It sounds like a tedius job...considering the stuff u already had in the tank too...like the sand and rocks and everything.

So, is there an easier way of doing water changes? Mabye my imagination is too much...lol...I just was wondering. Setting up the water again seems to take a while...to put in the octopuses tank.
Yes, there is an easier way, and I can see how you might get confused about it if no one has told you.

So you have your octo in his tank. First, you mix the salt water at least one day before. Test and adjust to get close to the water parameters of your tank - sg and pH. If you have a 50 gallon tank and do a 10% water change, that's 5 gallons. (You can use a 7-gallon empty salt bucket for mixing, pour in the RO/DI water, then the salt, and add a small pump to mix the water for a day. The water temperature should be about the same as the water in the tank.

Then, carry the bucket of prepared salt water to the tank. Have another empty 7 gallon bucket ready. Turn off all your pumps so that the water is quiet. (If you have a sump, some water will drain into the sump. ) Use a siphon and remove 5 gallons of water from the tank. You can do that without disturbing the octo usually, or maybe he'll want to play, so you'll need to be careful.

Then, use a pitcher that fits into the bucket, and start pouring water into the tank (my octo liked this part). When you get to the level where the water would begin flowing out the overflow, stop, turn on the pump, and have the pitcher reader to make an adjustment in the water level in the sump.

You never replace all the water. In fact 20% is a big change. You never have to remove the octo.

Other people will have slight variations on this - some pour the whole 5 gallon bucket in, but I'm not strong enough to do that, and it stirs up things a lot.

Hope that helps.

Thank you very much. Now I understand. At first...I was like...you gotta do a water change as in CHANGE the whole water inside the tank, lol.
But I guess only 10% or a few gallons of water change is WAY easier than doing the whole thing. And not having to remove the octopus from the tank is BIG releaf...considering that if you do remove it to do a water change...it will be hard cuz the octopus wont stay still if you put it in a bowl or bucket.

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