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FAQs about Shark Systems: Maintenance

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Related FAQs: Shark Tanks, Shark System Lighting, Shark Habitat (Substrates, Decor), Shark System Circulation & Aeration, Shark System Filtration, & Shark Systems 1, Shark Systems 2, Shark Systems 3, Shark Systems 4, Shark Systems 5, Shark Systems 6, Shark Systems 7, & Sharks in General, Shark Compatibility, Shark Behavior, Selection, Feeding, Diseases, Shark, Ray Eggs, Coldwater Sharks, Leopard Sharks, Heterodontus, Blacktip Sharks, Nurse Sharks, Moving Sharks

Water quality issues need to be monitored.
Metabolite accumulation, DO,
temperature especially.

Sharks and Rays in Aquariums
Gaining an understanding of how to keep these fishes in captive saltwater systems   

New Print and eBook on Amazon

by Robert (Bob) Fenner

High phosphates wither sharks      7/16/18
I have a 550 gallon salt water fish only tank. I two sharks approximately 2 feet long , epaulets and coral cat. I have been able to control the nitrates but not the phosphates, it us off the chart.
<Please tell me more about your tank equipment, other tank mates and maintenance practices.>
I am looking into hooking up a reactor with Phosguard but have read that some phosphate removers are not good with sharks. I was making sure Phosguard is okay to use with them.
<Phosphates are very hard to keep at low levels in Elasmobranch systems because of their feeding habits(amount and frequency). Fortunately high phosphate levels are tolerated by must shark species and YES, phosphate removers are toxic for them because of its ferric oxide composition which affects their electroreceptive system, I suggest you to use a deep sand bed refugium with algae(Chaeto/Caulerpa sp.) to keep phosphates in check; do frequent water changes and use a high quality skimmer rated to your tank gallon capacity to export nutrients before they break down.
Thank you
<You`re welcome. Wilberth>
Re: High phosphates wither sharks    7/17/18

I will try Phosguard thanks for your assistance.
<Let me know how it goes. Wilberth>

Re: Nitrate Reduction... f' also Lg. sys. maint., Shark sys....     9/15/13
... Are you joking? Re file size? Deleted. READ re our requirements, limitations... re-size and re-send all. B
Re: Nitrate Reduction    9/15/13

Ok,  Still working on the nitrate problem.   I have attached some pics of the sump and tank so you can see what I am working with.
<Have gone over all>
 I am looking at a few possibilities regarding this nitrate issue.   After reviewing the responses you have given me I am noticing I am very limited on what I can do.  Let me know what you think.    I have tried to figure a way to retrofit the bags but I have no way of setting them under the outflow pumps.   The sump was designed with an access tray that I was going to try to remove but could not I may be able to clip them to where the tray slides out by doubt it would be very effective.
<Do see CPR's site re:
  I do not have enough room in the sump for a refugium but I am going to have one built that I can tie into the main sump. 
Regarding that how many gallons does that sump need to be in order to be effective.
<As big as possible... whatever the largest size you can fit>
  In the meantime I have thought about pulling the matrix from the tank and cleaning it then placing it back into the sump.
  Would you recommend this or would this be more detrimental.
<Don't think it would make any difference at all; the washing... I'd just leave in place>
   I have noticed any heavy shifting can cause a nitrate and nitrite spike in my tank in the past.
<Shifting? Of what? How?>
  I have also noticed that since I have gone to changing the pads everyday that it almost seems pre mature since they look brand new when I pull the three floss pads out.  No staining at all.  Will an increase in water amount that I change per water change help to solve this problem. 
<Not much; no; and only temporarily... several hours to a day or so>
Possibly going from 100-150 gallons up to 200 gallons per week or even more or would that damage the stability of the tank.  
 I attached the pics so you can see the tank.  Everything is extremely healthy even the Duncans,  Mushroom Corals, Gorgonians and African Red Seastar.
  Maybe I am  over reacting but I just want to provide the best environment that I can for these guys.  PS.  I am using an API nitrate test kit and I have heard these test really high.
<I'd invest in a better make... API is really rudimentary... see WWM re such>
  I have three different test kits with API and have used all of them and they are all the same.  From your experience are these not accurate.
<Nor precise. Do get going on that 'fuge... add as much (a foot or more) of very fine sand... and alternating light cycle (RDP)... You're going to need all this, these changes, addenda as these fishes grow MUCH larger. Cheers, Bob Fenner>

Re: Nitrate Reduction    9/15/13
So to refresh
1.  Eliminate SeaChem matrix all together.
<Mmm, I'd keep it if I'd paid for it>
2.  Build as big a refugium as possible.
3.  Sand in refugium at a depth of one foot.
<Or deeper!>
4.  Increase weekly water changes to 200 gallons weekly.
<If you don't go broke or break your back!>
Is this accurate.
I assume you mean a one foot depth sand bed in the refugium.
<Ah yes. BobF>

Re: Nitrate Reduction; Shark Sys.      9/26/13
Leader of all that which is aquatic,
      Two things I thought of over the last few days that I would like your help on.
I have been thinking of adding a few more inches to the sand bed in the display tank.   Do you think this is a good idea with the sharks being large fish.
 <Yes I do>
Also.   I was wondering about adding a giant kelp plant
<... what species? Not temperate I hope/trust>
 into each of the four corners of my tank.  For two reasons.  I would assume the tangs could eat it but not faster than it would grow.  And it could be a very good looking addition to the interior of the tank and consume nitrates.
<Mmm, no... >
   The problem is I can not find any info of anyone keeping them in home aquariums and I cant find anyone that sells it.    Can you give me any info on either of these issues, it would be greatly appreciated.
<... the large brown (Phaeophyte) and red (Rhodophyte) algae that are kelps won't help here... Need to grow them, perhaps in a tumble culture in a separate sump/refugium... Have you been reading? B>
Shea B
Fw: Nitrate Reduction     9/26/13

Sorry I used the term Giant kelp.   Mainly a form of kelp with that look but smaller size.  Not sure if there even is one. Just so there is no confusion.  Sorry.
<No worries; there are many species... mostly too cold-water for your use... Do keep reading. B>

Hi Bob, I need your help please!
<Here for you amigo>
This week temperature went down here in Mexico City and my costumers shark tank drop to 70 degrees.
The tank is 1200 gallons housing a 30" 3 year old Blacktip Shark, the shark was eating and behaving normally all this time, water levels are:
Ammonia 0
Nitrite  0
Nitrate 0
Ph     7.7
<Mmm, a little low... I take it you use buffering compounds...>
Temp (before heater failure 78)

My guess is that the shark got hypothermia(let me know if I am right).we spend the whole night and part of this morning raising tank temperature, now it is 75 degrees but the shark barely swims and sinks on the bottom after just a few laps to the tank.
I grab it every time carefully and force him to swim, I increase aeration and last night add some ph up(Brightwell Aquatics) but don´t know what else to do, is it possible that having his temperature back to normal his muscles and other body organs work again or he is far gone?
Please help me the answer is not on your files, I was searching for hours.
Thanks a lot
<"Don't panic!" All should be fine w/in a day or two my friend. Go slow here w/ any changes. Nos vemos. RobertoF> 

Muchas gracias Bob, I´ll keep you posted
<Thank you, BobF>
Re: BLACKTIP SHARK HYPOTHERMIA, plus pH/Alk adjustment for large volumes    12/3/11

Hola Bob,
<Hey Wil!>
I want to tell you that the Blacktip is swimming normally again, like you said it took a couple of days.
I didn´t know they could get that bad at 70 degrees, I mean it is not really cold but they are tropicals hu.
The only problem to be solve is de Ph/Kh issue, I can´t raise it to the right levels, is there an effective product that you recommend?
<For 1,200 gallons... It may well behoove you to make your own. Formulations are available on the Net if you search. Otherwise, there are "bulk" suppliers, like BRS: http://www.bulkreefsupply.com/store/products/calcium-alkalinity-magnesium
In the long/er term, if this were my account, I'd be looking into a calcium reactor...>
Thanks for your help as always.
<Welcome. BobF>

Saltwater questions.. Shark sel., systems   3/4/06 Hi Bob, <Joe> I have a few more queries which I'd like your help for. <Will do my best> Firstly, I have a chance to purchase a Colclough's Shark, and knowing how rare these are, would like your opinion on whether these sharks might live well in my tank. <The genus does about as well as any captive shark species. Have never seen this fish in the trade in the U.S., but sometimes sold in areas closer to its Australian origin: http://filaman.ifm-geomar.de/Summary/SpeciesSummary.php?id=5893> My area of concern is the temperature range to which they are accustomed. Scott Michael's book states this range as being between 18 and 24 degrees Celsius. We have just come out of Summer in Australia and I have noted that the tank maintains an average temperature of about 28 -30 degrees Celsius. <Mmm, yes... I would employ a chilling mechanism here for sure> While I am certain that this will drop a few degrees during the winter, I do not want to purchase this shark only to let it suffer next summer. Do you think the shark will be comfortable given this temperature? <Not likely. We have a similar "challenge" here in S. California with folks trying to keep Leopard (Triakis semifasciata, now banned I'm given to understand), and our local Port Jackson (Heterodontus francisci)... some success during the winter months, almost none w/o chilled systems during the summer> If not, I would prefer getting an Epaulette which has a warmer range. <A better choice w/o the chiller...> Secondly, I am aware of a certain product on the market ("Deniballs T by Aquamedic) which claim to reduce nitrate by slowly dissolving over a period of a year or so. Is this product essential to a successful marine aquarium or is it simply a money burner? <Mmm... a worthwhile expedient for some... Nitrates can be a "menace"... but given other means, not necessary. You do want to keep these at a minimum in shark systems... less than 10 ppm.> Are water changes enough to control nitrate? <Well... not unless you're super-wealthy, to afford bunches of salt mix, or have a hose pipe from the sea to maintain an open system... Other means are detailed on WWM... Should be reviewed> Since I will be keeping a shark and ray, among other fish, do they have a specific low-tolerance to nitrate?? <Yes! Any is of trouble really...> Finally, are cooked shrimp better/worse than raw shrimp to feed to my fish? (In regards to nutrient value and disease carrying potential). <Worse nutritionally> Thank you very much for your time and effort, Joe <Thank you for helping us all by asking, sharing. Bob Fenner>

Outdoor Shark Pool... Heat Has Gotten To Querior   5/27/06 Hello, <Hi> Thank for all the great info on your website, its really appreciated.  
<Glad you enjoy it.>
 I have a question on having a outdoor shark pond/pool.  I was thinking of building an above ground pond (roughly 500 gal.) for a small shark (thinking banded bamboo shark) outside my house since an aquarium that size will be difficult to fit in my house.  I was wondering if the temperature of the Arizona heat will be difficult to keep the adequate temperature in the pond, not to mention evaporation.  I'm also wondering what kind of materials to build the pond out of and/or how big of a filtration system  will need.   Would this be a good home for a shark or am  crazy?? <You're crazy:)  You would have to have a very large chiller to accomplish this, and your electric bill would be as high as the Arizona heat.  Summer temps average in the nineties, often exceeding 100+ degrees as you well know, and to chill a tank down 20-25 degrees from ambient...Yowsie Wowsie.> Thanks. <You're welcome.  James (Salty Dog)>

Sharks in stingrays in a small tank - 3/15/04 I have an 80 gallon saltwater tank; it has been set up for about 2 years. I had a Blue spotted sting ray, and a black banded cat shark. <Much too big in the long run> The sting ray we have had for about a year. I don't know how old he was. The shark was about 2 months old; he was born into our tank from an egg. All of a sudden the sting ray just died no signs of foul play, only a small green mark on his belly. The shark died 2 days later. <Sorry to hear. Your description does nothing to implicate anything concrete> I could tell something was wrong with the shark a couple of days before he died, he was swimming erratically, and bumping into things, as if he couldn't tell which way was up or down. <Electrical current or magnetic field, metal poisonings, inadequate water chemistry, many things could be the issue here or a combination of them> The water tested fine. <Means nothing to me> The only thing I could think of is, it has been a while since I changed the filter in the wet dry, (about 2 months) apparently the filter needs to be changed every 3 weeks, I did not know that. <Hmmm.....maybe but not entirely convinced> If that is the reason why then why didn't my blue damsel die or my maroon clown fish? <That is easy. These are typically very hardy fish. Cartilaginous fish are very sensitive to water quality.> Looking forward to hearing from you. <Not sure what I can tell you here. Please read through our ever expanding section on sharks and rays for more information on nutrition, water quality needs, tank sizes, etc. Sorry I couldn't be of more help ~Paul> Cindy & George

Shark Tanks Aloha from Hawaii, <Howdy> My name is Jillian Davis, a junior at West Hawaii Exploration Academy (WHEA) on the Big Island of Hawaii. We have a unique school set up where we have access to surface ocean water and deep-sea water. <We were just visiting there (at NELHA) last week!> We just recently finished the tank for our shark pit, which is quite exciting. We also have an Aloha Kai program where students from other schools and people of all age groups come and see our projects. Shark Pit is intended to be one of the most exciting. Being that I have never had sharks before, I was wondering if you could give me some advice. These are the things I would like to know... <Okay> What is the standard temperature of a shark tank? <Mmm, actually, there are decidedly tropical to cool to coldwater sharks... and systems respectively. You can find ranges for many species listed on fishbase.org> How do we clean the tank or keep it from being over-grown with algae? <Good, thorough circulation/agitation of the water... I suspect you will have an open system (not-recirculating) otherwise we could chat re filtration methods... so good turnover (maybe ten-twenty turns an hour) will do likely... along with good scrubbing, vacuuming perhaps on a daily basis> What are some fish that would survive well in a tank full of sharks? <Depends on the shape, size of the system and types/species and sizes of sharks kept. I would try fast, aware species found in the same region/ecotype> Is there a certain type of fish that shouldn't be put in with the sharks? <Mmm, venomous, spiny types that might cause trouble if ingested> Are there any precautions we need to take prior to putting the sharks in the tank (water quality testing, etc.)? <Yes, please see below> Do you know of a source I can use to look up an future questions? <... Oh yes. On our site (starting here: http://www.wetwebmedia.com/sharks.htm and the materials listed in the bibliography/further reading at the end of the articles there. Do seek out Scott Michael's last re-do of "Sharks and Rays" for sure> Your time and effort in this is greatly appreciated. I would like to thank you in advance for any advice u may send to me. Mahalo, Jillian Davis 11th grade <You're welcome. Bob Fenner>

Re: Shark tank Saw/bought your book (TCMA) at our local pet shop this weekend. So hopefully, although you shouldn't expect fewer questions, perhaps you'll receive better informed ones. <Well-stated> Yes, very fond of fine specimens... Aquatic or otherwise. <Me too> If convenient (i.e. You have it in electronic form), I would greatly, hugely appreciate the opportunity to review the draft of Aquarium Sharks and Rays. But only if it's not too much trouble. <Hmm, have a draft copy (black and white, pages) and a bound finished... it's now in print... no electronic> Yes, the Ecowheel was a monster expense... But so are 100 gallon monthly water changes. Now, I'm only doing water changes every 3rd month to replace trace elements. Is this practice O.K. in your opinion?  <We'll soon see... should be... along with skimming> I DO change carbon and filter cartridges on a monthly basis. Other than eliminating nitrates and phosphates, which were previously a constant struggle to deal with, the other great benefit of the wheel is that it occasionally releases pieces of macro algae that my tang greedily jumps on. Since goatfish appear to eat anything they can get their mouths around, I'm thinking about getting small ones(s). Can you recommend number or goatfish and Archaster sp. stars for my tank? <Three of the smaller Goatfish species/individuals... and five or so Archaster> Thanks again, and looking forward to delving into your book. Looks tremendous from initial skim through! J.D. Hill <Yes, lots of good help putting these together. Bob Fenner>

Sharks and Rays in Aquariums
Gaining an understanding of how to keep these fishes in captive saltwater systems   

New Print and eBook on Amazon

by Robert (Bob) Fenner
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