I don't if Google is being updated to search less relevant stuff these days, but I just can't find anything on whether or not fish food/flakes are capable of releasing nutrients, vitamins, and/or minerals into the water column as it biodegrades over time in our filters... The reason I'd like to know is to save a couple of bucks from buying trace mineral supplementation. I don't really know if my tap water contains enough trace minerals, especially potassium.
Does fish food release nutrients into water column?
- Thread starter JRM592
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Yup, as it breaks down it will definitely release things into the water. Proteins, fats, all kinds of nutrients. Mostly what we're concerned about is what ends up rotting and producing ammonia of course.
Yes it does, like
TwoHedWlf
says. For example in reef keeping some people will ramp up their feeding to increase nutrients, which can have some benefits. In freshwater, nutrients can fuel plant growth, but generally they are less beneficial and usually better to keep water as "clean" as possible IMO.
TwoHedWlf
says. For example in reef keeping some people will ramp up their feeding to increase nutrients, which can have some benefits. In freshwater, nutrients can fuel plant growth, but generally they are less beneficial and usually better to keep water as "clean" as possible IMO.Hello; I have an unsupported notion but one that seems to fit in my experience. I have pretty much always kept snails in my freshwater tanks. My thinking being it is better for the excess/uneaten food to pass thru the gut of a snail rather than just to rot in the water. We run closed systems and have a partial understanding of the water chemistry with regard to ammonia, nitrate and nitrites. Enough understanding to run tanks well enough if we do sufficient water changes. We have test kits for a few of the compounds commonly found in closed water systems containing live animals. ( I sometimes get the impression we focus on the ones we can test for too much and pretend the rest do not matter.)
What kind of nutrients are you referring to? Various compounds and elements might be considered as nutrients for plants, or nutrients for bacteria, or nutrients actually intended for utilization by the fish (assuming they eat the food).
But I think it's pretty evident that food left uneaten in the water will be releasing all three categories into the water, both by breaking down and also by simple leaching of water-soluble compounds into the water. Flake foods break down quickly, and any soluble compounds they contain will dissolve quickly since the wafers are so thin. And if you doubt that this kind of stuff is getting into your water, just thaw out a chunk of frozen brine shrimp, bloodworms or any other frozen food in a glass of water before adding it to your tank. The solid particles settle quickly, leaving a fairly disgusting broth which will be dispersed into your tank if you feed your fish by the common expedient of just tossing a frozen cube or chunk into the tank. When the food is frozen, cell membranes are ruptured by expanding ice crystals; upon thawing, all that juice is released into the water, no longer accessible to the fish but nevertheless in your water. It's loaded with nutrients, all right...but it's about as beneficial as just peeing into your aquarium.
But I think it's pretty evident that food left uneaten in the water will be releasing all three categories into the water, both by breaking down and also by simple leaching of water-soluble compounds into the water. Flake foods break down quickly, and any soluble compounds they contain will dissolve quickly since the wafers are so thin. And if you doubt that this kind of stuff is getting into your water, just thaw out a chunk of frozen brine shrimp, bloodworms or any other frozen food in a glass of water before adding it to your tank. The solid particles settle quickly, leaving a fairly disgusting broth which will be dispersed into your tank if you feed your fish by the common expedient of just tossing a frozen cube or chunk into the tank. When the food is frozen, cell membranes are ruptured by expanding ice crystals; upon thawing, all that juice is released into the water, no longer accessible to the fish but nevertheless in your water. It's loaded with nutrients, all right...but it's about as beneficial as just peeing into your aquarium.
Even though we're talking minute ppm readings I believe just plain old water contains enough trace minerals to benefit your tank and it's inhabitants. And the best thing about it is we change our water regularly so we're always topping up these minute beneficial levels.
I'd have thought that uneaten decaying food, even though it might release some goodness into your tank, what I don't know, it will be releasing far much more badness, the main one obviously ammonia, to make it worthwhile relying on it as a method of mineral supplementation. Not only ammonia though but your water will probably be constantly cloudy, a smell may develop in time, and if you're dropping excess food into your tank your greedier fish will probably end up developing health problems through over eating.
Have a look at your local report, it'll give you a good idea on what's in your water.
I'd have thought that uneaten decaying food, even though it might release some goodness into your tank, what I don't know, it will be releasing far much more badness, the main one obviously ammonia, to make it worthwhile relying on it as a method of mineral supplementation. Not only ammonia though but your water will probably be constantly cloudy, a smell may develop in time, and if you're dropping excess food into your tank your greedier fish will probably end up developing health problems through over eating.
Have a look at your local report, it'll give you a good idea on what's in your water.
By far the largest nutrients released from rotting food will be the "unwanted kind",....., nitrate, and phosphorus
Nitrate would only be considered a desireable addition, if your tank has a much higher percentage of plants and very few fish and is nitrate deficient for the plant growth..
The way you replace the "necessary kind" is by doing water changes.
New water from water changes (depending on the buffering capacity of your source) can replaces buffers that help stabilize pH.
Waste production nutrients like nitrate tend to contribute to unstable pH, and other undesirable effects.
And the phosphorus rotting food adds, help grow undesirable kind of algae that compete with the of higher pants you may want in the tank.
Nitrate would only be considered a desireable addition, if your tank has a much higher percentage of plants and very few fish and is nitrate deficient for the plant growth..
The way you replace the "necessary kind" is by doing water changes.
New water from water changes (depending on the buffering capacity of your source) can replaces buffers that help stabilize pH.
Waste production nutrients like nitrate tend to contribute to unstable pH, and other undesirable effects.
And the phosphorus rotting food adds, help grow undesirable kind of algae that compete with the of higher pants you may want in the tank.
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+1 Besides good food, keeping very clean water is as good for your fish as anything. I don't claim to know the specific chemistry, but beside the downside, I wonder how much good minerals bound in fish food ingredients that sometimes require processing or synthesizing within the fish can do just sitting in the water.
At one time I experimented with adding expensive "trace mineral" water additives and experienced no difference at all to my fish. What did make a difference was feeding better foods, another thing I did extensive experimentation on. The only mineral additive that makes a difference to any of my fish is Epsom salts for my kapampa C. gibberosa. Lake Tanganyika is high in magnesium compared to the other African rift lakes and Epsom is a form of magnesium. The difference in color is subtle, but the more important difference is that some Cyphotilapia are susceptible to egg impaction and I've learned I can prevent it using Epsom salts, both with every water change and some extra to help spawning.
Cyphotilapia, and potentially certain other Tanganyika species, are an example of a specific fish that may benefit from specific minerals that may or may not be present or sufficient in your tap water. Another special case is you might want to add back minerals if you RO your water for fish other than blackwater species. Imo if you have particular fish and find a particular water supplement makes a difference, whether a commercially prepared formula or something simple, that's one thing. Otherwise, adding random, scattershot minerals to water when you don't know what's in it to begin with doesn't do much ime. Most fish do fine in most water with decent food, reasonable temps, pH, hardness, etc.
...Actually, blackwater fish are a good illustration. They often come from very mineral poor water. It's not that they don't need the same minerals as any other fish, but according to what I've read (aquaculture science, not forums), they're adapted with super efficient gills that lose very little of the minerals they absorb from food, etc.
While I'm on the subject, something else I've read is there's a misconception about how blackwater works. It's a case of people getting it backwards. It's not so much that the tannins in the water kill off most bacteria, it's that the mineral poor water support little in the way of bacteria. With few bacteria to break down plant matter and its humic (brown) and fulvic (yellow) acids, they're free to stain the water. So it's not so much the low pH that blackwater fish need to be healthy as a low bacteria load. At least that's the theory.
While I'm on the subject, something else I've read is there's a misconception about how blackwater works. It's a case of people getting it backwards. It's not so much that the tannins in the water kill off most bacteria, it's that the mineral poor water support little in the way of bacteria. With few bacteria to break down plant matter and its humic (brown) and fulvic (yellow) acids, they're free to stain the water. So it's not so much the low pH that blackwater fish need to be healthy as a low bacteria load. At least that's the theory.