Hippo Tang = UV light a must have?

Stu_Daddy03

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Hi, I’ve heard those fish are ich magnets. Should I buy a UV light before I get a dory fish then? I have a 120 total water volume tank (100 gal Innovative Marine DT and 40 sump - rocks and sand). Mixed reef set up with 2 clowns, 2 chromis, 1 rabbit faced, 1 yellow tang and 1 6 line wrasse. So looking to add a hippo tang and copper banded butterfly and a dwarf angelfish (this last three in one go to minimize aggression).
 

Ryan15236

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My hippo tang was one of the first fish added to my 180G. It was tiny when I got it. Size of half dollar now about 5 inches and thick in 18 months. It’s been a great fish and tough! It along with my longnose hawk and fox face survived a velvet outbreak that took out 15 other fish. It was not easy on it. It stayed hidden and didn’t eat much for weeks. Before the velvet out break it would get ich more than my other tangs but never slowed eating habits. I have since added a UV sterilizer to my tank (about 6 months ago) and my fish have never looked better. There is still ich in the tank but I rarely see a spot on any of my tangs. I should mention I am avoiding the most ich susceptible fish (acanthurus sp) because my tank is an “ich management” tank. This was the first UV sterilizer I have owned and I will never not run a tank without one. I would do yourself and your fish a favor and add one. If you get a UV get a DC controllable pump so you dial flow down to treat parasite and turn flow up to treat algae
 

SaltyBlue

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Great thing to be thinking about - personally prefer QT over UV, UV absolutely not required.

I would personally rather keep it out of the tank and QT all fish with the humblefish TTM or copper methods

My blue tang specific advice is it’s the shyest fish I’ve ever had in QT, laying on side on bottom all day, until I added a bunch of tall plastic plants
 

mcarroll

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Should I buy a UV light before I get a dory fish then?
You have a large "small tank". The Hippo is a fish stricktly for a 6' tank IMO – which is the smallest "large tank".

They need swimming room AND hiding room AND sleeping room like every fish, but they are much bigger than most fish. UV light won't change this. I won't do a tang in a tank that short, but if you MUST then select a smaller, hardier tang. IMO be satisfied with the Yellow Tang and hope it stays happy as it (and the other fish) grow.

If you want a REALLY blue fish (but aren't hung up on Dory), there are more suitable choices. Check out the Saphire Damselfish, for example. I have one and I am literally stunned by how blue it is every time it comes out. Seems to have no interest in the other fish, but then I make sure my fish have TONS of swimming and living space. (He's in a 125 with a clownfish. That's it.)

CB's are known trouble as well. Some folks get lucky, but SO MANY DO NOT and they lose the fish in short order.

Why risk it on these sketchy edge-case fish? Do you feel lucky?

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But seriously, you have a tank full of fish already. The risk is more than just that to the new fish. I would seriously reconsider the two big fish.

The dwarf angel is also a risk, but WAY BETTER than the other two IMO. At least with them the risk is mostly coral nibbling. They are the correct size for the tank tho.
 

CatBag

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Let's be abit real for a sec a small blue tang will take years to outgrow a 100 gallon, your fine adding one and watching it grow out. I have one in a 90 gallon got it like 5 cm in size and it's a decent medium sized fish now still doing amazing 3 years in got it with a purple tang same size. In my experience as long as you get a healthy fish that eats like a pig from the get go your fine without UV my tangs both show stress ich maybe like once a year when I move something or they decide it's time for a new boss to rule the tank but other than that they are all good. I had UV on for a year with them in and notice no difference without it on right now.

I do feed heavy though, pellets from a auto feeder 4 times a day, 2 cubes of frozen mysis or brine a day and a sheet of Nori every second day. My current stock is the blue tang, purple tang, clown pair, 5 chromis, flame hawkish, mandarine goby and Australian stripy.

I would be much more worried about the copperband you have aggressive eaters and it's not easy introducing them in last while everything is established the yellow tang might go straight for it because of the similar shape and colour.
 

CHSUB

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Uv is nearly worthless for ich…sure it will kill the few that make it into the filter but a diatom filter is far more effective however still nearly worthless. Your proposed fish additions are on the edge of overstocking depending on who comments. If you are going to proceed it is far more important to properly QT than adding a UV.
 

Techie_

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Fairly recently I had a battle with Ich and velvet at the same time. Not sure which fish or other live stock brought it in but the first thing I did was add UV and start a treatment regime. UV is the jab in a 1-2 combo to keep pests at bay. Ignore the tang police on this thread, a hippo is fine in your tank for a number of years if you get it small enough. Just be sure to rehome him appropriately. Regardless, UV is a great addition to your tank.
 

Lowell Lemon

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A lot of ignorance about proper use of UV from the medication crowd.

You will never have a sterile environment in any aquarium where you use live foods, frozen foods, or live rock and inverts.

UV limits the ability of the parasite to reproduce and lowers the count of parasites in the aquarium giving nature and the fish a fighting chance.

I designed and installed central filtration systems like the large wholesale fish operators use and it works when properly designed and deployed.
 

Jay Hemdal

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Hi, I’ve heard those fish are ich magnets. Should I buy a UV light before I get a dory fish then? I have a 120 total water volume tank (100 gal Innovative Marine DT and 40 sump - rocks and sand). Mixed reef set up with 2 clowns, 2 chromis, 1 rabbit faced, 1 yellow tang and 1 6 line wrasse. So looking to add a hippo tang and copper banded butterfly and a dwarf angelfish (this last three in one go to minimize aggression).

They aren't "ich magnets", not like the powder tangs are. What can happen is that they develop "mucus plugs" that resemble ich, but are different.

Don't rely on UV to control ich. Here is a write-up I did on that:

UV sterilizers

Ultraviolet (UV) sterilizers are also sold as a “cure” for Cryptocaryon. The problem is that most hobbyist-sized UV sterilizers do not have the power to make an effective kill on the relatively large Cryptocaryon parasite. Additionally, UV sterilizers are effective only on the tomite/theront stage, as this is the only point where the parasite is even present in the water column.

For velvet, Amyloodinium, the fallacy here is that tomites/theronts must leave the fish. Actually, some of them may get caught up in the fish’s mucus and stay attached until they become infective trophonts again. For Cryptocaryon, the tomites/theronts do seem to need to leave the fish, but with side stream application of UV (where only a portion of water passes through the unit) DWELL TIME becomes the limiting factor. Only a portion of the theronts are killed before enough of them attach to the fish to continue the infection. This means that UV sterilization will not eliminate active Cryptocaryon infections from a single aquarium. Where it does have benefit is in eliminating tomites as they pass through a filtration system from one discrete tank to another (like in a public aquarium or fisheries lab). Decades ago, diatom filters were touted as cures for ich and velvet. The same issue applies with them; there are adherent forms of these protozoans that can continue to infect the fish without ever having to leave the fish’s body. Even if they do, the same “dwell time” factor means that some theronts will still be present in the water column to infect the fish.

A recent study (Ge-Ling, 2022) indicates that the UV dose required to kill Cryptocaryon theronts/tomites is 185,000 uw/S/cm2. They do go on however, to conclude: “ …both ozone and UV are ineffective in controlling infection within an individual aquarium because of the adhesive nature of C. irritans tomonts (Ma et al., 2017). Therefore, the focus on UV and ozone treatment should prevent live theronts flow into aquaculture ponds. Second, the tomonts are strongly resistant to UV or ozone than theronts, implying that recommended production doses cannot wholly kill tomonts….”
 

mfinn

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I have never used a uv and I have always had hippo tangs.
Properly quarantined has been my go to method and as long as I follow the quarantine procedure I've never had a problem.
 

CHSUB

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I have never used a uv and I have always had hippo tangs.
Properly quarantined has been my go to method and as long as I follow the quarantine procedure I've never had a problem.
I agree, it is that easy. Not sure why there’s a debate?
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Stu_Daddy03

Stu_Daddy03

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Have you ever tried the tank transfer method opposed to quarantine with copper?
 

TheSaltyCPA

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Hi, I’ve heard those fish are ich magnets. Should I buy a UV light before I get a dory fish then? I have a 120 total water volume tank (100 gal Innovative Marine DT and 40 sump - rocks and sand). Mixed reef set up with 2 clowns, 2 chromis, 1 rabbit faced, 1 yellow tang and 1 6 line wrasse. So looking to add a hippo tang and copper banded butterfly and a dwarf angelfish (this last three in one go to minimize aggression).

They aren't "ich magnets", not like the powder tangs are. What can happen is that they develop "mucus plugs" that resemble ich, but are different.

Don't rely on UV to control ich. Here is a write-up I did on that:

UV sterilizers

Ultraviolet (UV) sterilizers are also sold as a “cure” for Cryptocaryon. The problem is that most hobbyist-sized UV sterilizers do not have the power to make an effective kill on the relatively large Cryptocaryon parasite. Additionally, UV sterilizers are effective only on the tomite/theront stage, as this is the only point where the parasite is even present in the water column.

For velvet, Amyloodinium, the fallacy here is that tomites/theronts must leave the fish. Actually, some of them may get caught up in the fish’s mucus and stay attached until they become infective trophonts again. For Cryptocaryon, the tomites/theronts do seem to need to leave the fish, but with side stream application of UV (where only a portion of water passes through the unit) DWELL TIME becomes the limiting factor. Only a portion of the theronts are killed before enough of them attach to the fish to continue the infection. This means that UV sterilization will not eliminate active Cryptocaryon infections from a single aquarium. Where it does have benefit is in eliminating tomites as they pass through a filtration system from one discrete tank to another (like in a public aquarium or fisheries lab). Decades ago, diatom filters were touted as cures for ich and velvet. The same issue applies with them; there are adherent forms of these protozoans that can continue to infect the fish without ever having to leave the fish’s body. Even if they do, the same “dwell time” factor means that some theronts will still be present in the water column to infect the fish.

A recent study (Ge-Ling, 2022) indicates that the UV dose required to kill Cryptocaryon theronts/tomites is 185,000 uw/S/cm2. They do go on however, to conclude: “ …both ozone and UV are ineffective in controlling infection within an individual aquarium because of the adhesive nature of C. irritans tomonts (Ma et al., 2017). Therefore, the focus on UV and ozone treatment should prevent live theronts flow into aquaculture ponds. Second, the tomonts are strongly resistant to UV or ozone than theronts, implying that recommended production doses cannot wholly kill tomonts….”
Do you ever get tired of reposting what seems to be almost common knowledge at this point? QT your fish people. It’s not hard!!!

UV doesn’t work. Also, I hate to be the bearer of bad news but 100 gallons is too small.
 

mcarroll

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I still don't get the confusion over how and if UV works.

Folks don't install it right or don't use it right and it doesn't work, I get that.....but that applies to everything.

We don't go around saying that aquariums don't work, just because some folks don't set them up right and they break.

Duh.

When installed properly (according to mfgr guidelines – no bypass, for example) the following is true....

UV light scrambles DNA.
It doesn't have to kill to be effective.
It doesn't have to be effective on the first pass through the filter.
Since the water recirculates thorugh the filter over and over, damage will accumulate with each pass.

Combining UV filtration with micron filtration is also smart – micron filtration is strong where UV is "weak". The larger the organism, the more susceptible it is to micron filtration – Crypto (not Ich, that's freshwater) is large.

UV+ozone is also smart in theory, but much harder to do safely compared to micron filtration, which is almost foolproof. For better or worse, most folks don't want to mess with ozone. (Ozone in saltwater seems to be a complicated topic.)

And it's not a "cure", it's prevention. Get it right. :)

As we know from Ben Franklin, "an ounce of prevention is worth a pound of cure."
 

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