Frozen Food

[hawkfish21]

I hope this question makes sense. What is the best technique for feeding frozen food? Does everyone drain the juice after thawing frozen food? I am currently thawing the food (Hikari) in RO/DI water in a cup, and then using a baster to feed. I guess I'm concerned that the juice in the food isn't so good for the water quality in my tank.

[GW Shark]

I understand that the liquid from frozen food can be quite high in phosphate. I thaw like you do, but I pour the liquid out through a brine shrimp net (couple bucks at the LFS) before feeding the fish.

[coralreef321]

I dont thaw it out and no problems. I think that there might be good stuff you dont want to drain. But I dont know

[LazyK]

If you have a good skimmer don't worry about the fluid. If you have corals you are probably robbing them of a good meal.
I thaw my food in a small amount of tank water, stir it up good, then pour it in. I also add cyclop-eeze 3 times/wk. My corals love feeding time.
My PO4 stays below .1ppm and nitrates are undetectable (Salifert tests).
Also, your refugium should suck up the phosphates.

[artful-dodger]

Anthony Calfo, in his All Things Salty forum, has frequently stated that the "juice" from brine, mysis, etc. should be discarded because of the nuiscence nutrients (algae food, not coral or fish food) it carries. Even though I frequently just feed it in a hurry, the best approach is straining through a small net as suggested by GW Shark above.

[fishetcinc]

I am going against the grain on this one.

Everyday, I feed all my fish frozen foods (either Marine Cusine, Emerald Entree, Angel & Butterfly Formula, or Spirulina Enriched Brine by SF Bay). I take the cubes and put them in a cup. I add Zoe, Zoecon, Vitamin C, and Garlic Extreme (one drop of each on each cube) and let it soak for about 15 min (ever walk in my store around 4PM? ... yup, that's why it smells like garlic in here ;)).

After soaking, I take some long tweezers, pick a 1/2 to a full cube, shake excess liquid off and tweezer-feed the cubes individually to each fish in the FO system. I then take the leftover "juice" and dump it all in the 1000g reef. Twice a week I add either phyto, zooplankton or cyclo-peeze into the "juice" before dumping it in the reef.

This is my theory. The "juice" is a concentrated medley of fat (specially omega -3 and DHA's), proteins, sugars, vitamins and trace elements too valuable to dump. In a FO or FOWLR system, you bet this is going to cause an algea bloom from hell because there is nothing in the water to absorb it other than algea. In a reef, these are essential nutrients for your corals and should not cause an algea bloom if your system is well-established and balanced (ie. good skimmer, lots of LR, working refugium, etc).

Now, I am not saying that the corals will directly eat the juice. Perhaps the fine filter feeders and some softies appreciate the loose nutrients in the water column but most of the juice will not be absorbed. So why do I put it in? My theory is that the "juice" indirectly feeds corals by providing nutrients to the naturally occuring cultures of plankton (rotifers, phytoplankton, zooplankton and other misc. larvae) in your LR. This, in turn, increases your tank's natural plankton concentrations which feeds your corals.

In nature, plankton feeds by swimming out into the water column whenever there is a surge in water-borne nutrients. This is when they become available as food to corals. I see this behavior everyday in my tank. About 10-15 minutes after I dump the "juice" into the tank, the tank suddenly gets a bit cloudy and all the corals open about 2-3 times their normal size and all the feeder tentacles pop out. My hypothesis is that they are feeding on the live plankton that has come out to the water colum from the LR to feed on the loose "juice".

As for algea, I have not experienced any outbreaks from this practice. I am dosing about 1 cup of "juice" per 1000g every day which comes out to 2ml per 10gal. The only thing I watch out for is too keep an eye on pH/Alk since the juice is very acidic. Keeping my Alk at 11dKH via buffers keeps a stable pH 8.4.

One warning though. Some frozen food brands do use triphosphates as a perservative (usually on krill, mysis, clam) so the juice from these foods will cause an algea outbreak in any tank since you would be adding excessive phosphates. I think this is what Anthony Calfo fears. I use SF Bay Brand since I know they do not add triphosphates (or alteast not enought to affect a phosphate test :rolleyes: )


K.

[artful-dodger]

Thanks, Kei. Good input. (Now I can stop feeling guilty when I don't strain the food 'cause I'm in a hurry!) I never have had an algae problem since the tank was a couple of months old (knock wood!) so I have not been overly concerned. Your logic is reasonable. You can't argue with success (and you can always change practices if unsuccessful.)