Chopped fish vs pellets and water quality

[jaws7777]

Do you guys who feed chopped fish such as tilapia, market shrimp or any other meaty foods notice a difference in water quality, specifically nitrates vs feeding pellets ?


I mainly feed my carnivores chopped tilapia soaked in bvc and the fish produce much less solid waste (poop) than when i feed pellets.

So what do you think has a greater impact in terms of nitrate production ?

 

[esoxlucius]

All food will lead to nitrates, whether it's uneaten food gone bad or eaten food that gets pooped out, we all have to deal with that. However, high protein diets lead to increased levels of nitrate, hence protein skimmers in marine set ups to keep the nitrates as low to zero as possible.

 

[RD.]

I mainly feed my carnivores chopped tilapia soaked in bvc and the fish produce much less solid waste (poop) than when i feed pellets.

This is due to the fact that volume wise, fresh/frozen contains approx. 70-80% water. Also, fresh fish contains zero carbs/starch, so typically it is more fully assimilated compared to most pellets. Most fish can uitilize "some" carbs in the diet (as a source of energy), but it is typically not an essential nutrient. Generally speaking the more carnivorous the species of fish, the less carbs that the fish can properly digest and utilize. The rest comes out the other end ......

 

[jaws7777]

All food will lead to nitrates, whether it's uneaten food gone bad or eaten food that gets pooped out, we all have to deal with that. However, high protein diets lead to increased levels of nitrate, hence protein skimmers in marine set ups to keep the nitrates as low to zero as possible.

Thx for the reply man, i get that all food leads to nitrates but was wondering what people thought produced more nitrates pellets or chopped fish.

This is due to the fact that volume wise, fresh/frozen contains approx. 70-80% water. Also, fresh fish contains zero carbs/starch, so typically it is more fully assimilated compared to most pellets. Most fish can uitilize "some" carbs in the diet (as a source of energy), but it is typically not an essential nutrient. Generally speaking the more carnivorous the species of fish, the less carbs that the fish can properly digest and utilize. The rest comes out the other end ......

Thx neil, that explains the huge mess i find when i go pellet heavy.

Do you think theres a difference between the two in terms of nitrates ?

 

[Drstrangelove]

Nitrates are directly a result protein.

Gram for gram there should be no difference afaik, but of course the volume has to be converted to dry weight and protein content to get apples to apples.

All protein is of course not identical. Nitrogen content (which breaks down to ammonia in animals) varies from ~ 10 - 20 %, although normal averages are more like 16%. So it's not technically a high versus low protein content, but a high versus low nitrogen content comparison.

We of course are privy to the actual nitrogen content in most otc fish foods, but there tables that do describe content for common animals. I had a source table somewhere which I'll attach if I can.

As far as volume is concerned, the other issue is that most ammonia is excreted through the gills, with most of the rest defecated, (part is maintained for biological reasons), so it's possible that the proportions are different in excretion vs defecation based upon the type of food.

This course isn't the same as pellets containing more undigested items which could cause a lot of the issues since that isn't excreted. The more in the food that can't be consumed (or excreted), the more that has to be defecated.

 

[Drstrangelove]

http://www.jbc.org/content/159/2/373.full.pdf

So this isn't the table, but one can see that individual "base" proteins vary by nitrogen content widely 8-27%.

This would imply that various foods with the same protein %, but that are made up of different proportions of the base proteins, would have different amounts of nitrogen and thus different amounts of ammonia. Ammonia is directly a pre cursor to nitrates.

 

[jaws7777]

http://www.jbc.org/content/159/2/373.full.pdf

So this isn't the table, but one can see that individual "base" proteins vary by nitrogen content widely 8-27%.

This would imply that various foods with the same protein %, but that are made up of different proportions of the base proteins, would have different amounts of nitrogen and thus different amounts of ammonia. Ammonia is directly a pre cursor to nitrates.

Thanka for the explanation Doc.

I think i assumed that since the chopped fish looked dirtier (oils left in the water) it would actually be dirtier (nitrate)

 

[RD.]

the volume has to be converted to dry weight and protein content to get apples to apples.

I agree with the good doctor, one can really only compare foods on a dry matter basis. That is precisely why I stated that fresh fish contains 70-80% water content. Water is a non nutrient.

 

[Dieselhybrid]

I find the type of fish matters as well. Feeding shrimp and firmer white fish seems to preserve my water quality well. I catch most of the fish I feed so I have tried many species. I have found that cod and pollock really flake into tiny filament like hairs and foul the mechanical filtration quickly. Denser fish like perch, bass, halibut and trout/salmon (tilapia is dense also) really hold together better, making less scrap particles that don't float and end up in my filtration system. You also have to consider oily fish that leave that film and rind at the surface. I have found that anchovies and smelt really contribute to this even though their flesh stays solid and doesn't flake much as much as lingcod or pollock.

I'll never feed cod again, it was disastrous to my water quality with flakes floating everywhere.

I find the same can happen with pellets if you feed too large of a pellet size. I think people feed way too large pellets to their fish. They figure since they are eating aggressively things must be fine. They fail to notice the massive amount of pellet waste being pushed out of the gills and mouth while the fish is choking down big pellets. I think using appropriately sized pellets can cut down on waste if feeding dry. RD. has touch on this many times over the years.

I only feed fish and shrimp/crawfish to adult fish currently. I have spent a fortune on pellets and with around 40 rays I feed a great deal of food. I use pellets for smaller pups and juvenile rays but would break the bank feeding pellets to all of the herd.

I use USA sushi and sashimi standard when preparing fish. Freeze at minimum -5f for 120 hours to "cold cook" and kill potential parasites and pathogens. Or -40f for 24-48 hours, the standard vary by state but if you use a prolonged deep freeze you can help your catches be food safe.

 

[jaws7777]

I find the type of fish matters as well. Feeding shrimp and firmer white fish seems to preserve my water quality well. I catch most of the fish I feed so I have tried many species. I have found that cod and pollock really flake into tiny filament like hairs and foul the mechanical filtration quickly. Denser fish like perch, bass, halibut and trout/salmon (tilapia is dense also) really hold together better, making less scrap particles that don't float and end up in my filtration system. You also have to consider oily fish that leave that film and rind at the surface. I have found that anchovies and smelt really contribute to this even though their flesh stays solid and doesn't flake much as much as lingcod or pollock.

I'll never feed cod again, it was disastrous to my water quality with flakes floating everywhere.

I find the same can happen with pellets if you feed too large of a pellet size. I think people feed way too large pellets to their fish. They figure since they are eating aggressively things must be fine. They fail to notice the massive amount of pellet waste being pushed out of the gills and mouth while the fish is choking down big pellets. I think using appropriately sized pellets can cut down on waste if feeding dry. RD. has touch on this many times over the years.

I only feed fish and shrimp/crawfish to adult fish currently. I have spent a fortune on pellets and with around 40 rays I feed a great deal of food. I use pellets for smaller pups and juvenile rays but would break the bank feeding pellets to all of the herd.

I use USA sushi and sashimi standard when preparing fish. Freeze at minimum -5f for 120 hours to "cold cook" and kill potential parasites and pathogens. Or -40f for 24-48 hours, the standard vary by state but if you use a prolonged deep freeze you can help your catches be food safe.

I never tried cod but noticed that flounder doesnt hope up well and creates a huge mess. Same with silver sides.


Thx for the explanation guys