REDSTEVEO said:
..I have never thought about obtaining a water report for this area of North Wales. Might be interesting reading and as you rightly pointed out if the stuff is already in the water what's the point of buying and adding more.
Yeah, it's always worth having a look. The usefulness of each report differs because of reporting styles I was looking at a Dee Valley report for someone and it looks like that area has lowish-to-midling TDS, which kind of implies softer and low nutrient content water. There's a wide range in that municipal zone though. I would definitely start with the baseline dosing as well as the addition of a little Calcium and Magnesium. You can always withdraw these two later on if you want, and look for any negative effects.
REDSTEVEO said:
Bye the way, just like the previous post, I too am curious as to what you do for a living.
Oh, Well, believe it or not, I started life as a Test Engineer. Now I'm a struggling Gangsta Rapper. I do a little freelance science on the side, you know, just to pay the bills....
Ady34 said:
..Ive read the thread again but am confusing myself with numbers so would like to know from someone who does it regularly roughly what amounts of the n, p, k and csm+b i should be dosing in teaspoons on the appropriate days.
Obviously if its getting down to 1/16 then im guessing its ok to accidentally add a little more as its not exact....i just want to keep it somewhere near as i dont want uneccessary rises in tds.
Hi Ady,
Well, again, I always try to keep it simple, and I always worry about plant health first before moving on to worrying about other parameters. If a tank is 50 gallons, I round it up to 60 gallons. That way it's exactly 3X the size of the reference 20 gallon tank and I can simply multiply the reference dosing number by 3 and round up or down to a convenient teaspoon measure.
So the reference 20G KNO3 dosing is 3/16 teaspoon thrice a week. If I multiply that by 3, I get 9/16 teaspoon right? Well, 9/16 is close enough to 1/2, so why not just round down and dose 1/2 a teaspoon thrice a week? Then, for the KH2PO4 just dose 1/4 teaspoon and do the same for the trace. That will get you started on the right track and will keep you out of trouble.
When people start talking about "unnecessary parameter changes" that's when I get off the bus, because that's how people get into trouble. They fall into a mode of thinking whereby the nutrient dosing becomes a fall guy for the things that they imagine to be problematic. Poor plant health is a bigger problem than unnecessary TDS rise. How about thinking in terms of unnecessary starvation, or unnecessary algae?
When you observe after three weeks or so that the plants are doing well, and that there are no deficiency syndromes, then it's a good time to think about lowering the TDS. If you want to be precise and systematic in how you lower TDS then a good idea it to use one of those test kit vials, you know, the small graduated cylinder? It has "ml" markings in white. Measure how many ml of powder is actually in your "eyeballed" 1/2 teaspoon for example. You can also use a scale to weigh the powder as well. Measure your TDS regularly and plot on a graph via spreadsheet the weekly TDS profile of the tank. It will go up and down as you feed, dose nutrients, add medicine, change water and do other things to the tank.
Now you have a baseline profile for comparison. Then, reduce the powders by some arbitrary amount, say 10% - something easy to measure consistently, either via the graduated cylinder or on the scale. Dose that value for three weeks and observe the plants. Measure the TDS and plot the it's graph. If no deficiencies are noted after three weeks then reduce the powder dosages by another arbitrary amount. Repeat the exercise until you note some deficiency, all the while continuing to generate TDS profile plots. You'll then have the data that shows you the gradual decline in TDS profile, each plot should be labeled with a name indicating the dosing level responsible for that plot.
At some point you will see the minimum dosing level required to avoid deficiency for that tank and for that lighting level. it will show you what the resulting "necessary TDS" for your dosing program is.
Cheers,