Hm… I bet that would work as a regular maintenance measure… I bet you have a lot of calcium carbonate buildup though if your heat exchanger is not functioning properly anymore. 
Use the highest % acetic acid by volume that you can get your hands on. White kitchen vinegar is usually 7%. But you can buy industrial grade that is 45% or even 75%. (Use caution, eye protection, gloves, etc. of course!)
(I assume the manual says what % is safe to use.)
White vinegar is 5%, or at least that’s the only strength I’ve ever seen. Next common strength would be agricultural vinegar, which is 20% or thereabouts.
Oh, I think mine is 7%. But I’ve also seen El Cheapo brand at 4.5%, which is disappointing when you go to use it to can with, and you can’t. Can. 
I’ve seen picking vinegar as high as 10%. Anything higher isn’t edible. (10% isn’t really edible either, lol.)
We finally got gutsy enough to do the first attempt at descaling the water heater.
Success is unclear lol.
We did approx. 4 gallons of white vinegar pumped through it for maybe 10 minutes. 
First shower was “better” (aka I had consistent hot water for a full 5 minutes) but it started going back to its old ways by the end of the shower. Time will tell if we need to do it more, for longer, or if I go back to trying to find someone to look at it proper.
eta: Our white vinegar was 5% acidity, as @druidessie indicated. It’s all I could find.
Recommendations for RF dog trackers for those of us with fewer than 20 dogs? I would go with Garmin if I had a hunting pack, but all I want is to track two little escape artists while they help us find all the weaknesses in the fence. So far they haven’t gone out of earshot, but they will if they scare up a herd of deer on an expedition.
We need RF rather than bluetooth or cellular because of lack of signal.
Does anyone know anything about Apple trees? I’m not sure if ours counts as mature or not. It definitely isn’t “first year” but it’s also still really small. I’m having a hard time figuring out what I’m supposed to do with it.
Main thing would be pruning, I think. You want to remove crossing branches and I think I remember something about certain kinds of “crotch” angles (angle where branch meets the trunk) being weaker and therefore undesirable in a mature tree. There’s also multiple schools of thought on how to shape trees but that goes way over my head. I’ve mostly left my couple remaining trees alone, for better or worse.
I don’t know if there’s any spraying you want to do with apples before it’s actually producing fruit, but your local extension service would be the best bet I think.
I’m so conflicted on pruning- it’s got 4 different apple types grafted on, and I’m scared I’ll remove too much of one of the types. This tree came with the house and I’m super overwhelmed lol. I’ve only tried fruit trees once, when I was like 8, and they died 
Ignore all the toddler water play objects lol.
Apple trees you typically want to prune to a central leader structure (as opposed to, eg., peaches which are often pruned to an open vase). Esme is right about crossing branches. However, never prune during the growing season, do it when dormant. I don’t know what you do with multi graft trees though. Narrow branch angles are less desirable than those that are closer to right angles (more prone to splitting). You can even buy branch spaces to help encourage this growth habit.
How tall is it? Do you have the original tags? It is possible it is a dwarf or ultra-dwarf…
Oh also, usually you can see the grafts on a grafted tree. Check around google for images. 
I’m probably a little over half the height, maybe 10’? Hard to tell. This is all for the original tags:
It’s too bad the tag doesn’t have the nursery name, “combination apple” is just generic for a multi-graft tree.
10’ is decently tall though, dwarf apples are typically 10-12’. Semi-dwarf are typically 12-15’ and I don’t imagine a local nursery would sell a standard multi-graft tree (in fact, they often don’t sell standard trees at all, even many commercial orchards are switching over to semi-dwarf). So it could be full size, or nearly there, already. Dwarfs and semi-dwarfs typically take 3-4 years to reach maturity and start bearing. It is often recommended that the first few years in the ground that you pinch off all developing fruit so that the tree puts more energy into the root system, making it a stronger, healthier tree. I’ll probably leave a couple my first few years. It’s too bad you don’t know how old it is. It might be old enough to just leave alone.
I believe with apples, you want to thin fruit as they develop, in the late spring. Usually apples are borne in clusters, and by thinning to only one fruit per cluster, you get bigger fruit (and also, if you don’t thin, you will often get boom-bust with yields (ie one year you get a ton, the next year almost nothing, rinse and repeat).
Apples are in fact susceptible to coddling moth (and some other things), and the extension service will usually have a service that you sign up for text or email alerts when to spray for certain things (they monitor and send alerts when the traps start catching things, so you are not spraying prematurely or without cause). If you don’t want to spray, you’ll want to bag the fruit when coddling moth are detected, to prevent the moth from laying eggs on the developing apples (this is how you end up with worms in your apples). No-spray fruit are quite difficult to produce without manual work (like bagging fruit), because there are a lot of pests (plum curculio and apple maggot flies I think are the other two major ones). (That isn’t to say you can’t eat it, you just have to cut around the bad parts.)
Having said all that, your tree looks quite nice! I would probably just monitor and see what it does this year.
Thank you so much!!! That helps a TON. I just haven’t had the bandwidth to focus on or process anything about this.
One other thing to be aware of is pests chewing on the bark (or mechanical damage to the bark), because if a tree is completely girded (the bark stripped all the way around in a ring) the tree will die, as that is where the vascular system is. (So try not to hit it with the lawn mower, it looks like it is near the edge of the lawn… actually, I think I personally would remove the grass farther from the trunk so this doesn’t happen). But I think since you are in a neighborhood with fences there’s probably little chance of deer coming through and eating the bark (winter usually) or rubbing against it. (Plus it is fairly small for them to want to do that?)
Disclaimer, I have no idea how much this translates to a different tree species, but we recently had an arborist out to look at our crepe myrtle that was getting overrun by moss. The arborist said the groundcover we had (viney stuff, not grass) needed to be cut back at least two feet away from the trunk because it was using up all the ground resources and the tree was struggling because of it, which made it easier for the moss to take over instead of the tree being able to fend off the moss to reasonable levels.
tl;dr - your tree will probably appreciate having a bit more breathing room from the grass, in addition to keeping it safe from lawn maintenance injuries.
We currently have a massive 30+ year old cherry tree that we’re probably gonna have to cut down because the previous owner ran over a bunch with the lawnmower 
So alas, I am well aware of this problem. We definitely do need to do a bunch of grass maintenance and pull it back. It looks more overgrown than it is from the angle, there is like a foot or a foot and a half of mainly clear soil around it. But I need to get some groundcover in there. I need to figure out what I can do for mulch that is in a massive sliver risk, since it’s right in the prime baby play area.
OMG. Well, I know how you feel, I have seen all the receipts from the house renovation for this house over the year before I bought it (I don’t know why they provided everything to the lawyer rather than just the relevant well and septic, but I’ll take it!!) and they had cut down 3 cherry trees and a cider apple. The receipt says the cherry trees were dead (which they may have been), but still.
For mulch… maybe in the short term you could use something like that rubber playground mulch for just that area? It could block weeds but allow water flow, and also not be a sliver risk. 
She would eat it so it needs to be something safe from the front as well. Playground wood chips may be my best bet, even though I think they’re ugly. I’m worried straw would hold too much water, plus we live in a wind corridor.
O geez!
Cocoa shell mulch? Pine needle mulch?
ETA: cocoa shell mulch is a bad idea if you have dogs (that might eat it).
“Tabies” are hard mode. (Toddler/babies). She has zero capacity for self control, still puts everything in her mouth, but can run, climb, etc. This age is hard mode. Especially Latte- she’s on the upper end of physical prowess and height, but lower end of “we don’t fucking eat plastic”.
