I’ll give some extra clarification since you’re new, and other newbies might read your post and need clarification.
You should not run SH ‘through’ your machine. In other words, you should NOT have a supply tank or SH injector BEFORE the pump. There’s just lots of parts inside the machine that don’t do well with SH and it will increase the likelihood of pump failure.
The alternative is to run the SH ‘after’ your machine, instead of through it. That little “T-shaped doohickey with the clear-ish hose” that you’ve connected after your pump is a Hi-draw Downstream Injector, and is the perfect way to add chemicals to your mix.
At lower PSI and flow, the injector will inject 1 part of whatever is in the bucket it is connected to, into about 5-10 parts of water flowing through your pump. As mentioned above, you can do an injector test to see how much your injector is drawing.
Scenario 1: For a housewash where you are trying to get 0.75% SH on the house, and an injector with a 10:1 ratio, your injector supply bucket would need 7.5% SH. To achieve this you’d mix the 12.5% SH with water in your bucket to get you to 7.5%. (ie, 1.25 gallon SH mixed with 1 gallon of water, and a splash of Elemonator (1 oz).) Many pros don’t do all that fancy measuring, and use a more diluted mix, see if it turns organic material brown within 5 min. If yes, continue using. If no, increase the mix strength by adding more SH to your downstream supply bucket.
Scenario 2: for post treating a driveway you surface clean, you may want to put down a strong 3% mix on the concrete. With a 10:1 ratio, your injector supply bucket should be around 30% SH. Aw, drats! You can’t buy it that concentrated. So your injector won’t work. With a 10:1 ratio, with your downstream supply bucket as pure SH (storebought at 12.5%), the max you can downstream is 1.25%. Luckily, that’ll do for a post-treat. Just not as effective as a stronger mix which would take a 12v system or X-jet.
Hot Tip #1: to keep the injector intake at the bottom of your supply bucket put some weight on it, or route it through a section of PVC pipe so that it stays straight in the bucket.
Hot tip #2: Once you are done using the downstream injector, put the intake in a bucket of clean water to rinse out the inside, which will make it last longer.
Hot tip #3: Buy a spare injector… that one will break in the middle of your most important job. (You don’t have to buy the whole kit. Just the brass injector part.)
Hot tip #4: the injector reduces flow. When you aren’t actively using it, remove it from your setup to maximize flow.
Good luck and welcome to PWR!