Phosphate that won't go away

[srusso]

Appart from the P level, any noticeable differences? Coloration/pe/growth/..

Its funny you should mention that, the tools I normally use aren't effectively cleaning the screen this last harvest. Growth seems much more attached, and doesn't cut/break apart easily any more.

[Ace25]

My phosphates yesterday were .17 after a 'moderate' feeding the day before. Moderate for me is 1/2 of what I normally feed, so 5 cubes of food instead of 10. I am trying to do my tests at the same time everyday in order to exclude any variables that 'ATS lighting schedule' may create. I am testing at 4pm, which is midway through the dark cycle of my ATS.

As for color, polyps, growth... too early to tell for me, I *think* the colors are looking slightly more vibrant, but I know the human eye is not a good tool to tell that stuff so it could certainly just be wishful thinking. No change in polyp extension or growth that I can see so far.

[kerry]

Test my 150G UAS and its still at 20PPM nitrate and about .25-.50PPM phosphate by the API kits. I also tested my my 40G waterfall and its zero nitrate and still shows yellow in the phosphate API kit, its not dead on yellow but a slightly darker hue of yellow so I am calling it 0.0ish???? Regardless, its zero-ish as is always is.

[Garf]

Anyone fancy a read ;
http://lakewatch.ifas.ufl.edu/circpdffolder/nutrpt2.pdf

[Floyd R Turbo]

I just have to pass on that I was just advised by someone to be very careful with potassium dosing. There are many K test kits out there, and I was told that the Elos kit was probably the most accurate out of all of them. Like many test kits, these are good at tracking trends, and some are reliably accurate, but when it comes to Potassium test kits, this is apparently the one that has one of the lowest reliability/accuracies, and if you overdose on K, bad things can happen.

So TEST before you dose, bottom line.

One of the indicators he said was red monti caps. If they are not fading in color, then it is doubtful there is a severe depletion in K.

However, when I told him that my Sailfert kit showed K=350, he said if that indeed was accurate, that was really low. 390-410 is where it should be. My tank is 350 and the other tank (dentist's office) is 325, both with red caps, both are doing fine. So I don't know what that says, but I'm getting the Elos kit before starting to dose.

As always though, with everything - know before you dose.

[kerry]

Good info!!! I have held off on ordering anything so far. I have Grape Monti caps which look really more brown/redish then grape color and they are doing awesome but, thats the 40G waterfall that runs perfect even if I lag behind on dosing Kalk.
I was looking for info on how much an average reef tank used of potassium in a week or month time but came up kinda empty as I figured I would. They say to dose Strontium and iodine to about half of what they say on the package but I might dose what the package says about every 2 months and don't see any problems. So is potassium going to be about the same??? If these tests are not so accurate or hard to read as the reviews say what is a good indicator?? Is it going to be the phosphate readings? This leaves me a little gun shy to do anything with it!!!

[Garf]

Can't understand why in fertilisers, the N is usually higher than K. Wouldn't this mean there is still plenty K in a tank reading 300 say (unless nitrates are about 1000)! This is in relation to N P K ratios.

[srusso]

I, of course live on the edge, dosing and watching for slight changes.

Added another 20ml today.

I know the P's are really low right now. I don't let the glass get very bad ever, but going this long without seeing any growth at all is crazy... Cleaned the glass on Tuesday and it looks as clean today.

I will test tomorrow.

[srusso]

Can't understand why in fertilisers, the N is usually higher than K. Wouldn't this mean there is still plenty K in a tank reading 300 say (unless nitrates are about 1000)! This is in relation to N P K ratios.

This is because the plant will over time need more nitrate then any other nutrient.

[Garf]

This is because the plant will over time need more nitrate then any other nutrient.

Yeah. But if nitrate is say 1ppm, then K only needs to be 0.3ppm to maintain balance, and not the 400ppm available in seawater.

This analysis shows that potassium is 30 times less abundant in algae as iron is;
Table 18.2. Composition of multin (i.e. dried powder of Spirulina fusiformis) (constituents are in per 100 of powder)*.

A. Major constituents (%)		C. Minerals (mg)
Total protein	64.6	Calcium	6.58
Fat	6.7	Phosphorus	977
Crude fiber ;	9.3	Iron	44.7
Carbohydrates	16.1	Sodium	796
Calories	346	Potassium	1.28
B. Vitamins		D. Essential amino acids (%)
Beta - carotene	320,000IU	Lysin	2.99
Biotin	0.22 mg	Cystine	0.474
Cyanocobalamin (B12)	65.7 mg	Methionine	1.38
Folic acid	17.6 mg	Phenylalanine	2.87
Riboflavin	1.78 mg	Threonine	3.04
Thiamin	0.118 mg
Tocopherol	0.773 IU