Usually the all are a teaspoon per gallon. I use a ppm meter ti nitrate my poisonous brew. Since I water almost daily when it's warm, I want no more than an 150ppm change. Since I use a Siphonex which is supposed to dilute the mix 16 to 1 but in reality does other depending on water pressure, size of hose etc I measur the tap ppm, then the ppm of what comes out of the hose. I add enough of whatever to give a 150 ppm rise. In reality, I only do this now and then as a check since once it's dialed in, it never changes.

I don't know what the change should be if you water once a week, I suspect around 300 to 400. Measure the ppm of the water source, add 1 tspn per gallon and measure again. adjust to get the desired range. If you don't have a ppm device go to a place that sells water and act interested in their product, they'll test for you.

Nick

Thank You orchidnick! I appreciate it! I have no ppm gauge so a teaspoon per gallon or less is it. Thanks so much!

Here is a fertilizer calculator.

Full strength for most fertilizers is usually around 120ppm nitrogen. That would be about 1/3 teaspoon per gallon for your 30-10-10. And of course half strength would then be 1/6 tsp, and quarter strength 1/12 tsp. It may be hard to measure 1/6 and 1/12 tsp unless it came with a small scoop for those amounts.