Sodium tripolyphosphate; Is supermarket shrimp safe for marine fish?  4/5/07
Is the sodium tripolyphosphate found in supermarket frozen raw shrimp safe for marine fish?<I wouldn’t use anything with it in it. Depending on what livestock you’re feeding, I’d go with frozen krill, or similar, available through your local fish/pet store. Sodium tripolyphosphate, or STPP, is a chemical preservative that has the added merchant bonus of increasing the sellable weight of a product. It also makes seafood taste funny! We don’t need it and neither do our little fishy friends!>Thank you for your time.<You're welcome! -Lynn>

Live food for puffers? (03/10/04)
Hi,
<Hi! Ananda here tonight...>
Is there any risk of passing on disease to my puffer if I feed him scallops, shrimp, etc. purchased still alive from my local supermarket?
<Unfortunately, yes. Kelly the Puffer Queen once mentioned she'd traced a puffer death to something transmitted via freshwater mussels she'd fed to the fish. You can't assume that any wild-caught food is safe for your puffer. If you do choose to buy the live food, I would suggest quarantining it for a month or so before you feed it to the puffer. Otherwise, freezing the food for a few days to a week should take care of most pathogens, protozoans, etc. that the critters might carry.>
Thank you.
<Thanks for asking -- I'm always glad to help prevent puffer illness! --Ananda>

Reef feeding question (copper as an ingredient in foods)
I have a 120 gallon reef system and have been feeding primarily frozen Formula One for some time.  All species of fish in my tank have done very well on the Formula One.  I recently purchased a new batch and noticed on the label that one of the trace elements listed in the ingredients is copper sulfate.  Should I be concerned about copper buildup in the system?  I've trusted the reputation of Formula One and am not sure what other frozen options should be considered.  What would you recommend?
<No problem. The copper amount is of no consequence here. You won't be able to measure it>
I appreciate all the help and good advice I find in your forums every week.
<Ah, good. Be chatting, Bob Fenner>
Thanks,
Scott

Starving Goby (1/27/04)
  Hey guys- I have a watchmen goby who appears to be starving to death. <signs & symptoms?> the only food I can offer is staple flake enriched w/ Selcon and a refugium (newly set up). <Why not frozen foods?> I read on your articles advising of nutritional deficiency and was wondering if there is anything I can do to nurse sally back to health. thanks again Justin Barstow's <A new refugium is not likely to be putting out anything useful yet. Some of these gobies will take flake/pellet foods. Others will not. Are there competitors in the tank that eat everything before it gets down to the goby? I'd suggest target feeding with frozen Mysis shrimp or other frozen marine foods. The Selcon is a good idea too. Hope this helps, Steve Allen.>

...about that copper sulfate...
Good evening WWM crew! 
<Good Evening Teyah!> Hope you all are well. <Just peachy so far!>
A couple of nights ago I discovered that some pellets I was feeding my cleaner shrimp had copper sulfate in them. While this doesn't seem to have adversely affected the shrimp, I wanted to discontinue using the product. Prime Reef was suggested as another possible source of food, and indeed I've read/heard lots of good things about this frozen food. 
<Comes in flake version as well w/o Copper Sulfate. (At least the plastic jar/jug I have).>
Tonight, however, I discovered that one of the ingredients (trace elements) in this is copper sulfate. So... just how harmful is copper sulfate to inverts if given in this form? Since it says right on the package that this stuff is "ideal for reef systems", & given that I've heard of other people feeding it to their shrimp/inverts, that leads me to believe that it can't be THAT bad. What's the word guys? Should I feed it to them or not? Thanks for the advice/time patience! Have a great night! TJ
<Well your shrimp should be proud of you for thinking of them and doing such a great job of reading the labels! I wouldn't feed this food or the darned brine shrimp pellets either! Frozen marine meats like those available from your local fish store will do nicely, or frozen or flake foods w/o copper sulfate.
Keep reading those labels and enjoy your shrimp! Craig>

Trigger Live Food
I have a question regarding Trigger food --- basically I am trying to find a live food to feed my Huma and Undulated Trigger --- my experience is that live food triggers (excuse the pun) a instinctive response in predators that you don't get with frozen, pellet or flake food (just my experience with triggers and Groupers when I had across the street access to crayfish).
<You and I's experiences are in agreement>
  The reaction when a my trigger is fed a live crayfish or night crawler is noticeably different than when they see a frozen silverside, flake or pellet food.  That leads me to my question --- I have 8 Bearded Dragons
<For unfamiliar readers these are lizards>
and their main diet is Crickets (farm raised no pesticides) --- now here is the catch --- to gut load the crickets I feed them fish food --- I know you know where I am going with this. Is there a problem with feeding the triggers the gut loaded crickets? ---
I already know they will eat them readily my Huma devoured about 12 medium crickets yesterday.  Pros or Cons or absolutely not?
<Likely no difficulty... other than the very response, conditioning you alluded to initially. Do you want your fishes to "act mean"? If so, feeding live foods will encourage this. Bob Fenner>

Copper sulfate in food
Today I tried to feed Kent Platinum reef pellet food to my fish. My pepp. and cleaner shrimp ate it instead. They loved it! I then read ingredients, and copper sulfate is listed, along with other vitamins, etc... Could this harm my inverts and my copper sensitive porcupine puffer? Thanks for your help, Laura
<I doubt that it is enough to harm the fish, although all best are off on the inverts. Nonetheless, with so many great food choices out there... consider and alternative since you have copper sensitive livestock just to play it safe. Kind regards, Anthony Calfo>

Frozen Food & Skimming
Dear WWM Crew,
Hope everyone had a good holiday. I have a question about some frozen foods I had ordered. I decided to stock up on some frozen foods from an online retailer and everything had arrived defrosted. Probably not a
good idea to order in 95 degree heat. The Formula One, Two, Spirulina and Angel Formulas were still cool, but they were almost like soup. The clams and squid were pretty much thawed as well. The dry ice was completely evaporated also. I have re-froze everything and it looks fine but I called two pet shops and they both told me to dump it. So, valuing your advice more I'm asking: Can this food be salvaged or should I dump it?
<Dump it my friend.>
One more question if you would. I started using a Polyfilter about a month ago, and ever since my skimmers produce very little skimmate now. Would I be better off not using the Polyfilter and let the skimmers go to work?
<This maybe unrelated. Do try cleaning your skimmer and its pump thoroughly, including a run in a hot water and vinegar bath to remove deposits. This usually vastly improves performance on skimmers that have been running for over six months.>
The Polyfilter is not necessary so I'm wondering if it would be better to let the skimmers take the crud out before it has a chance to break down. Thanks in advance, Mike
<Have a nice evening. -Steven Pro>

Gelatin-based foods - 2/12/03
Greetings Krewe!!!
<whassup G-money?>
I continue to have algae problems in my 20 Gallon mini-reef. My water parameters are good - 0 Ammonia, 0 Nitrates, 0 Nitrites, 8.2 Ph. I'm changing about 3 gallons per week with pre-mixed and aerated water.
<all good>
The only abnormal parameter is low Calcium. Will/can increasing Calcium in tank help with algae?
<the calcium does not per se (other than long term support of desirable calcifying algae that can out-compete nuisance forms)... however, some calcium like Kalkwasser can precipitate phosphates and raise pH which both immediately inhibit some nuisance algae>
What's the best method for this size tank?
<likely bigger water changes actually>
I have been doing my best to reduce nutrient import. I feed twice weekly with a mix of Formula 1, Formula 2, and Mysis.
<The Formula foods are good... but messy>
Export is via Remora Pro skimmer and macro algae in hang-on refugium.
<awesome>
Today's FAQ's have a reply from Anthony in reply to draining frozen
food: "Gelatin based foods cannot be treated this way... of course, gelatin based foods are also catch-22 and arguably not the best fare either. Best regards, Anthony"
I am doing my best to drain my food, but I'm still having trouble. Are the Formula brand foods gelatin-based?
<yep>
Am I suffering from gelatin-based food syndrome??
<likely not for the fine skimmer you have can temper it... there is some other nutrient issue at hand IMO. Does the skimmer work well (several cups of skimmate weekly in this case?)>
One more quick question - I'm having trouble finding a good method to block large pieces of algae and bubbles from flowing back into the tank while still allowing copepods and other small organisms to return to the main tank. Thoughts, ideas?
<not sure... is this an upstream or downstream refugium? Assumedly upstream? At any rate, neither the bubbles or algae should exist... we need to stop them at the source. I fear that your algae is Caulerpa or some other easily fragmented form (even the fine Gracilaria). Do consider a more stable macro in this case like Chaetomorpha>
Thanks! -Jeremy
<best regards, Anthony>

I love your BOOK!
Dear Bob,
My name is Sean. I am sort of new at this and thought I knew a little bit but when I finished your book, The Conscientious Marine Aquarist, I was totally amazed! Wow dude you are BAD! (In the cool generation X'er kind of way!)
<Thanks for pumping me up!>
I did have two questions though and since I just got off vacation (I read your book two times!) I have not gone through your whole site to find if these have been posted before.
<Me neither!> 
My first question is this: At one point in the book you mention to stay away from Gelatin based foods and another part about homemade foods mentioned Gelatin. Can you help me to clear this up?
<Thanks for pointing this out... yes to trying other emulsifiers, preservatives like alginates... overuse of gelatins can be a "bad thing" (with a nod to Martha Stewart)... but rarely causes problems in systems that are properly maintained (gravel vacuumed, water changed...)>
Thanks a million for your great book. I doubly enjoyed my vacation because of it! I would buy anything you write. Have you ever thought of being more specific to name brands of certain Items that you personally use? (i.e. protein skimmers for 125 gallon tanks?) Some of the different types and styles confuse me and I would rather do it right the first time. Thanks again.
<Hmm good questions... have listed my opinions to most all makes, models of any gear used in the FAQ sections of our websites pages/articles: Home Page ... and hope to be doing something more in the way of offering such "favorites" in the near future.>
Sean
>>
<Be chatting my friend,
Bob Fenner>

Prime reef
Have you ever heard of toxicity problems associated with Prime Reef flake foods?
<Hmm, no...>
Although I can hardly believe it, this food has killed in a spectacular fashion, many of my fish, mostly hawks. By spectacular I mean the fish immediately goes into convulsions, swimming wildly without control until dead a few seconds later. I also lost a Sailfin tang the same way. I've ruled out any other possibilities by water changes, salt mfg. changes and dechlorinator changes. These deaths occurred in different tanks at different times with only one thing in common, the food. All occurred immediately after consuming Prime Reef. If you have any corroborating information please let me know. Thanks.
<This is my first exposure with any reports of this sort... have you contacted the manufacturer? Had your food sample tested by a lab? I would do both. Bob Fenner>

Re: potassium and prime reef
Hello Bob. I wrote you earlier today describing the violent deaths of many of my fish immediately after they had eaten Prime Reef flake food. As I was reading the ingredient list on the can, I noticed at least two sources of potassium. I soften my water supply with potassium chloride salt to remove the calcium which carries an excessive amount of radium. 
<Really? Fascinating...>
Do you think it is possible that excess potassium in the aquarium water when combined with the food might have a toxic effect?
<Quite a thesis... but no... not likely as far as anything I know...>
Has anyone ever studied the effects of potassium on marine tropicals? 
<Am very sure there are such studies... an essential nutrient... you could/will cause a stir with adding another "test" here...>
Is the amount of potassium found in water softened with KCl dangerous to fish? 
<If not dangerous to... than not likely to your livestock...>
If you can offer any information I would really appreciate it . Thanks again.
<I can only refer you to existing texts on "Fish Foods", encourage you to pursue a search of the scientific literature on toxicity of Potassium, its salts... on aquatic life... go see a college reference librarian with your query. They can/will help you with a computer search of existing knowledge. Bob Fenner>

Quick Question
Hi Bob,
<Hi there>
 I'm swimming in a sea of boxes right now. I am going back and forth between this place and my new place moving stuff. Quick question for ya about fishy stuff.
How long is frozen fish food in the freezer good for?
<Almost indefinitely... at least several months>
How long is Amquel and the like good for?
<Even longer...>
Trying to figure out if I should move them or just toss them in the garbage...
<I'd keep, use both as long as they "don't smell bad">
Thanks!
Madison
<Chat with you soon my friend. Bob Fenner, just back from FLA>

Thawed Fish Food
Mr. Fenner,
I've emailed in the past about more serious fish matters, but this is a minor one. I thank you in advance for your help.
I seem to have a bad habit of leaving frozen shrimp packages out. This evening, I left a full package of frozen plankton, and a mostly full package of brine shrimp out for ~5 hours. They thawed through, but are packaged in plastic bubbles with aluminum foil sealing them. In the past I've thrown them out, but is that really necessary?
<In general not in my opinion. Unless there is obvious "rot" as in smelly decomposition, I suspect marine and freshwater animals encounter such states of "freshness" in the wild>
I feel silly about having to ask, but with the frequency I do this, it could get quite costly.
Thanks very much,
John Sanders
<No question asked in sincerity is silly. Be chatting my friend. Bob Fenner>
John M. Sanders