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How bad is city tap water?

Yup, looking at RO systems now.

What would you think of Cuprisorb? Seachem - CupriSorb

Seems like it may do a job along with poly pads of maybe making the tank acceptable.

Looking at also buying the seachem copper test which tests to less than 0.01mg/l, which is still a lot more than the .00038 found in seawater but it may be a start.

Still learning how to gauge topping off but so far I think it's been OK. What about topping off salt?

Thanks
 
The CupriSorb is an interesting resin but I have no experience with it. The quick check I did came up with no negative reviews and a lot of evidence that it helps remove copper from tanks treated with copper medications (never do this to a saltwater display tank). Levels of removal are not quantified at the low values believed to be necessary but I believe it is worth a try. You will need to find a VERY fine bag (I believe it also comes prebagged) for the product as the grains are TINY. Any bag that suggests it will hold Purigen will have a fine enough mesh. If you see it turning blue or tinged with blue you will know it is working but you will also know your copper levels are very dangerous.

Saltwater is not topped off but removed and replaced. You will need a siphon hose, preferably self priming (something like this), a 5 gallon pail with a handle (remember this will weigh about 40 pounds. Good exercise but you may want to consider dumping it halfway through the process), a turkey baster (yes, kitchen appliance that looks like a tube with a rubber bulb at one end). After your initial cycle you will start your water changes. Once you have an octopus, you will need to do them more frequently (once a week recommended and 5 gallons is about 10% and the minimum - I usually do 10 gallons a week on a 65 gallon+ sump system with an octo in residence. For comparisons to other discussions rank your tank as a heavily stocked 30 gallon fish tank and not a single occupant species only 50 with sump - octopuses are messy). When you siphon off your water, you will want to attempt to remove debris as well as water. Fan/blow on the rock (with a water moving pump, turkey baster or by hand) to move settled waste into the water column and use you siphon to capture what you can ( this will also help it move to your primary filter). I also vacuum and disrupt the bottom substrate (sand) at this time.

Another grocery store item to pickup (in addition to the turkey baster) that proves invaluable for many things - feeding an octopus among them - is a pack of bamboo skewers. 100 will cost you somewhere between one and two dollars and will last a long time.

Note that the links are for visual reference only, these are grocery store/dollar store items with no special requirements (turkey baster should be glass or plastic, avoid metals).
 
Thanks Dwhatley.

I'm all set to go. I bought curprisorb, a fine mesh bag and the seachem copper test. Since the cuprisorb can be reused hopefully I will see a good result doing it a few times.

I'm confused about the topping off issue though. When I had my aquarium setup I was told to top it off with water maybe once a week or every two weeks, or as I see it going down.

From what you wrote it looks like I shouldn't worry about replacing the water till after the cycle is done. Does that mean I should not be topping it off at all?

That's definitely a post I will have to come back to and read again when it's time.
 
You are confusing topping off with freshwater and water changes with saltwater. These are unrealated maintenance procedures. You top off to keep the same salt concentration as the water evaporates (salt does not evaporate). We top off daily or every other day depending on the time of year.

You do a water change by taking out existing dirty saltwater and replacing it with the same amount of new, clean saltwater. In the process of changing the water you want to stir up the detritus that settles to help get it out of the aquarium.

If you start a water change and the water is low, you will need to add freshwater to keep the same salt concentration. You can measure the saltwater you take out, replace the same amount and then top off with fresh or top off first, and refill to the full point, either way you always exchange salt for salt and top off with fresh. You will need RO/DI water for both.
 
OK, thanks. Yes I was confused as I hadn't hadn't realized I will have to change the salt water out. I am preparing for this buy buying all the equipment.

Is it correct that salt does not have to be added when topping off, and the levels are maintained when doing the water change.

Is it advised to do a salt test to ensure the levels are correct?
 
I bought a 7 stage RO/DI system, so that won't be a concern anymore.

The seachem copper test didn't show any copper which was odd..will do it again to make sure I got it right.

Curpisorb hasn't turned blue yet...so will see what happens.

How important is it to test for salt levels? If salt doesn't evaporate and I put enough in when doing the water changes it should be OK, right?
 
While you are cycling, if your salinity about 34 (between 1.024 and 1.026 specific gravity) then you are good until you start adding critters (as long as any water changes test at the same salinity). However, over time you will notice salt caking in areas where you have splashing. We call this salt creep and it will reduce your salinity over time so once you have animals in the tank you will want to be sure you salinity is constant. If it starts to get low, topping off with saltwater is usually enough to gently adjust.

Inverts and corals need to be kept at a higher salinity (closer to ocean levels) than fish so I would check your set up to make sure your installer did not make this oversight. Most fish keepers use a target of 1.021 to reduce the risk of parasites but this is not healthy for corals and inverts where it does not give the fish problems.

Before you add critters, you will also want to be sure you PH is between 8.4 and 8.6 (there are test strips available to test this).
 
Excellent, thank you.

Is there a salinity refractors you recommend or it doesn't matter?

I found both a Pygmy and Caribbean reef octopus for sale. Thinking the pygmy would be a good fit for my 56 gallon when it's ready.
 
I am not the best person to make a recommendation for a refractometer. I never seem to get them to calibrate well and use a much simpler hydrometer to check my water. After using 4 or 5 different brands, I find the Instant Ocean unit to be the most consistent but you do have to keep it clean, rinse it with fresh water immediately after each use and be sure you release trapped air. There are many who wrinkle their noses at this type of device but it is my preference. There are also glass floating combination hydrometer/thermometers that I strongly recommend avoiding since they float in the tank, are easily broken and hard to read.

O. mercatoris (Caribbean pygmy) is not for everyone. They are nocturnal and rather shy. There are a couple of interesting advantages to them though in that you can keep multiples (size compatibility is a consideration and multiples should have been caught together and be about the same size) and they will mate and produce offspring in the tank. Currently, @sedna is experimenting with keeping multiples in her Mercatoris Manor .

You can keep O. briareus. Your tank will be just under the minimum size we recommend but, with the sump, it is doable. This species is also a night active species but more likely to be seen during the day as it ages and learns an early feeding time. It is arguably one of the most attractive species and one of my favorite. Currently @TMoct is attempting to raise hatchlings produced from Iris, the wild caught adult O. briareus received in January.
 
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DWhatley, Just wanted to thank you for your reply as always. I ended up getting a refractometer that was very highly rated on Amazon so will see how it goes.

I did some more reading and indeed O. briareus seems perhaps more appropriate.
 
I just wanted to make an update. I've been doing water changes as a precaution, but my TDS meter reads 7ppm from water straight out of my tab. Copper tests come up negative as well, for what ever that's worth.

I'm in Williamsburg, NYC for a point of reference.
 
Nice to know your water appears to be as good for drinking as advertised but don't use it straight up for the tank. When I see 6 on my RO water, it is time to change the RO filter but I start out at about 34 on the TDS meter.
 

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