Conducting a Food test for PO4

[rayjay]

It's not trace elements you're removing with PWC's but excess nutrients.

No, in my case I'm removing trace element build up as well as excess nutrient like the phophates mentioned above.
In addition to nutrients, foods we feed our tanks contain trace elements, including iodine forms, much the same as the foods we feed animals, including for instance, cattle.
When the foods exit the animals as waste, the waste releases to the ground, the trace elements that come with it, only to be taken up by whatever grows in the ground it is deposited on.
The same happens in our tanks as the fish wastes and tank detritus release to the water various trace elements AND nutrients as they decomposes, and these nutrients and elements are taken up by anything that feed upon them.

 

[tecwzrd]

Although every one I know uses snails and many have hermits, I don't have either in any of my tanks, and my tanks are bare bottom.

Not having a cleanup crew is all the more reason you should limit your feedings to every other day. Most fish will loose interest in flake/frozen quickly once it’s on the bottom unless you have bottom feeders and excess food needs to be cleaned up constantly.

I agree that most people I know as well are feeding daily and if in small quantities is perfectly acceptable. Some of it has to do with the species they keep as well since certain species of SW fish need to be fed daily and sometime 2-3 time a day in small quantities.

Personally I have been feeding my fish every other day for 15+ years including FW, Brackish, & SW. Most adult fish can easily go for 3-4 days without eating and keeping them slightly underfed but not undernourished is good for them because it keeps them more active and grazing on a more natural diet of what they find in the lr.

Also fish do not know when they are “full” right away and will often exceed taking in more food if offered which can lead to lethargy and health problems over time.

As I stated before whether feeding daily or every other day if your fish are consuming all the food offered within 30 seconds the amount should be increased slightly, if not consumed within 3-5 minutes then decreased.

If you over feed your fish you can immediately see the bad results in dirty water, bad water chemistry, algae growth, etc.

A lot of flake and frozen have iodine and vitamins added for the fishes health but contribute very little in actual “trace elements” added to the tank.

Natural SW mostly contains Cl/Na/Mg/Sulphur/Ca in larger quantities and hundreds of others in smaller quantities.

The food we add mostly gets eaten by fish/mobile inverts and most elements/vitamins are absorbed by them and exported. Fish/invert waste has little elements left and mostly just fouls up the tank with excess organics/nutrients which is replaced by doing PWC.

 

[rayjay]

"Not having a cleanup crew is all the more reason you should limit your feedings to every other day."

My way has worked fine for 12 yrs + and for 10 tanks totalling 590g plus sumps.

"A lot of flake and frozen have iodine and vitamins added for the fishes health but contribute very little in actual “trace elements” added to the tank. "
Trace elements are not added to the foods, they are naturally present as is iodine.
As these foods are broken down by either decomposition, or by the natural process in the fish (and others) digestive system, the trace elements are released into the water, and then can be utilized by tank inhabitants, including algae.

"Natural SW mostly contains Cl/Na/Mg/Sulphur/Ca in larger quantities and hundreds of others in smaller quantities."

Yes, I make up my own salt water for use in my brine shrimp growing operation and, I mix it 50/50 with IO for my fish only tanks. I use only the major salts and don't add trace.
Sodium Chloride, Magnesium Chloride Hexahydrate, Sodium Sulphate, Calcium Chloride, and Baked Baking Soda to help the alkalinity. (thanks to Randy Holmes-Farley for his help)

"The food we add mostly gets eaten by fish/mobile inverts and most elements/vitamins are absorbed by them and exported. Fish/invert waste has little elements left and mostly just fouls up the tank with excess organics/nutrients which is replaced by doing PWC."

Nothing can be exported from the system without physically removing it, as in water changes, harvesting macro, vacuuming detritus, etc......
Elements put into a tank are not used up to be non- existent, they are still there, just as the phosphates and other organic materials are still there until removed. The elements and organics can change in form, but unless they somehow are converted to a gaseous state, they can't exit the tank on their own.

 

[tecwzrd]

As I said feeding daily and if in small quantities is perfectly acceptable.

When I said export I was trying to use a nicer term for “poop”. Fish food that has been digested is much less an element contributor then undigested food.

Iodine is depleted by skimming and needs to be replenished, not exported for those with dense populations of invertebrates or soft corals.

About the only thing needing to be removed by doing a PWC is the end result of the waste (mostly no3) which is why it’s important to limit waste as much as possible by feeding sparingly (daily or every other day) and with proper skimming.

 

[rayjay]

I guess we'll have to agree to disagree.
I am considered to be a very heavy feeder but my systems still function fine.
Digested fish food waste is only lesser in element content by what the fish absorbs into his system which for the most part will also be expelled as urine or in it's stool at a later point. Otherwise the fish would become toxic.
RC had a thread about the results of water testing done on hobbyist water that showed the trace elements almost always far exceeded NSW limits. I'll try to find that thread if I can get their darned search thing to work.
I'm not sure that it would still be there now that Dr. Ron Shimek is gone, but hopefully so.
Dr Ron is another that espoused water changes to lower nutrient and trace elements.
I guess, like many other things in this hobby, there are many different ways that work for many people, so as long as what I do works for me, and what you do works for you, that's all that really matters.

 

[DragonForce]

This is why i feed pellet. Every peice of food gets eaten in about 3 minutes so it have very minimal impact on the water quality.

 

[seaham358]

pellet is nice but variety IMO is needed so the fish get all the nutrients they need. I feed some flake, nori, cyclopeeze, mysis and brein and some times golden pearls.. I do not feed these all at once I spread it out over time.. I do feed something every day...