[PRSRocker3390]

Right now i fertilize using dry ferts mixed in a 250ml distilled water solution. I dose using ml because i didnt have measuring spoons to do small measurements like 1/16th of a tablespoon of dry fert. I think dry ferts are easier and might be more accurate so I was thinking of getting a gram scale to accurately measure. Anyone know where I can get a reliable but cheap basic scale to use? I found this one on ebay, http://cgi.ebay.com/500-0-1g-GRAM-D...in_0?hash=item27ab062043&_trksid=p3286.c0.m14

Also, my dry plantex CSM is stored in a dry dark cabinet in a ziplock container. I recently noticed some blueish green specs in it and white specs too. Is this normal?

 

[markstanfill88]

Cant beat a 100% feedback. Its cheap, Id try it. Dunno about the specks in your csm tho. Ive not had any show up. If I was guessing I would say a little moisture got in and a metal is turning that color.

 

[Darkblade48]

The problem with any of those cheap digital gram scales is the fact that they are subject to "creeping digit" syndrome; i.e. you weigh an object, and after a while, the weight slowly increases "magically". In addition, they are not very accurate (i.e. if you take the weight of an object 10 times, the weight will not always be the same each time), and require frequent calibration.

I suppose they work fine for EI, since it really is estimative anyway.

As for the CSM+B, I keep mine in a tight plastic container in the dark and also notice blue/green spots as well as white spots. It hasn't deterred me from using it

 

[PRSRocker3390]

does dosing dry work better or is it more effective than using mixed liquids?

 

[marineboy]

PSRocker
Try this site http://www.wholesale-scales.com/index.php?main_page=product_info&cPath=1&products_id=402 and search for this scale Fast Weigh TS-100 Digital Pocket Scale 100 x 0.01 gram This is the one I got and it is more accuarate which is what I was told you needed 0.01

 

[Darkblade48]

For our hobby, you really only need to 0.1g. Anything more is just overkill.

I also would question the accuracy and reproducibility of the measurements from that scale. 0.01g accuracy for $9 is "too good to be true"

 

[Hoppy]

Most of us, I think, try to be sure none of the needed nutrients is in short supply at any time in our tanks. In other words we dose to get non-limiting concentrations of all of the nutrients. That means we intentionally dose more than the plants are likely to need. Then, about once a week we do a 50% or so water change to get rid of any excess of any of the nutrients. That is the Estimative Index method, and accuracy in that method is pointless. The ordinary tiny measuring spoons you can buy at various stores, are accurate enough.

It makes no difference whether you dose the dry fertilizers by dumping them dry into the tank, or mixing them with water first, and if you mix them with water it doesn't matter whether you use tap water or distilled/deionized water. However, a very few folks have really bad tap water, with more nitrates in it than is recommended for human consumption. For those, it makes some sense to use distilled or deionized water.

 

[Indignation]

For our hobby, you really only need to 0.1g. Anything more is just overkill.

I would add a caveat to this, as this is true for larger tanks but not very small aquariums. for example, on a 2.5 gallon .1g of kh2po4 adds 7.37 ppm... About 3.5 times the recommended weekly amount, per EI.

 

[Darkblade48]

Nano tanks are another beast entirely

I'm not sure whether EI is recommended for nano tanks or not, since their small size means things can go out of control very quickly.

 

[Indignation]

Sure hope it is, as I've been running a 2.5 with EI for a month.

And it just dawned on me that a .1g scale used to make a solution with DI water would work just fine, even with very small tanks.

 

[jreich]

almost all digi scales are susceptable to "digital creep" but i allways test the accuracy with either a nickle (5 cents) or the calabration weight it comes with. if it does not come with a calabration tool its probably a piece of crap.

 

[Cbwmn]

I use a balance scale.
Years ago I bought a small balance scale for my son's cub scout "Pinewood Derby"
race car. That balance scale has to be adjusted to read "zero" prior to weighing anything. At the time it was very accurate, because each car was weighed on an official scale before the race. His car was right on.
Hobby stores sell them. And fairly cheap.
It is made by the Diversified Scale Co., Inc.
It's a "Counter Balance" #CB500.
The scale readings can be changed to read:
Weight in ounces
Weight in metric
Weight in metric, 1/2 kilo
Postal rates
Weight in troy
If you google the company, it will probably show up.
Charles

 

[VisionQuest28]

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250437257724&ssPageName=STRK:MEWNX:IT Thats the scale i bought, it was an or best offer deal...i ended paying around $23 shipped for it. Its been great. Has maintained accuracy, and if you way the same object over and over its within .01 grams everytime. I have only been using it for a little over a month though, but it comes with a 10 year warranty. If you do some searching for good pocket scales you will see there is actually a whole enthusiast sub culture..there is a TON of info out there. If you want a reliable scale go with a trusted name...there are a lot of fairly cheap options out there, just go with a tried and true scale. The jennings scale i got came highly recommended and so far im extremely happy with it.

 

[Left C]

I bought a 200g/0.1g Sper Scientific Pocket Balance 100006 from AquaticEco.com. I've been pleased with its service.
http://www.aquaticeco.com/subcategories/3402/Pocket-Balance/pocket balance/0
http://www.sperscientific.com/images/broc_pdf/100006.pdf

I have another digital scale that measures to 0.001g for making reference solutions, dKH solutions, etc.

 

[Left C]

... i didnt have measuring spoons to do small measurements like 1/16th of a tablespoon of dry fert. ...

I got some stainless steel smigen, dash and pinch spoons at Bed, Bath and Beyond for $3. That's 1/8, 1/16, and 1/32 teaspoons.

If you are dosing EI, using spoons may be accurate enough instead of making solutions. But, solutions can be more accurate though.