I've got a radiator in the loop. The original question was, would a fishtank chiller work without condensation and the answer was, yes it won't go below ambient.
However I would try the radiator in the loop before buying the fishtank chiller.
There are many options in this kind of loop I could upgrade the cpu block, the pvc tubing to 15mm id (but since the narrowest point is 10mm and the cpu block it won't improve the flow any?) the radiator, the reservoir, or the fans or the pump.
The reservoir we have got to a bathtub size, 125litres may not be enough but it is 10x more than what I'm using at the moment, and the radiator could go to a 240, 360 or 420mm but as it will probably be aluminium I'd get galvanic corrosion against the cpu block so I'd have to switch that to an aluminium one and maybe lose some efficiency.
a noctua nh-d14 would eliminate a lot of the hassles for the same price as a chiller, like the loop and I still don't know which option would top out the overclock. I dunno if I would also have to lap the heat sink base, but that would be even more hassle, I couldn't get a rather convex arctic freezer pro to sand flat on 36 grit even after a couple of hours it wasn't getting anywhere.
I did lap and polish both the cpu block and cpu but they were both relatively flat to start with.
I wouldn't get a quiet pump that is that is any larger than the aquarium pump I'm using at the moment in the same price range, of £15.
So the cpu block, the tubing, and pump won't be changed it's the rez. and the rad. and the fan with the option of removing the rad for fishtank chiller.
The rez. is the cheapest shot, and I would need it to be larger for the fishtank chiller, and since a new radiator is probly aluminium I don't want one.
If the larger rez. and fan don't work for £40ish I don't think it can all be upgraded for less than £100 so why not buy an all in one at this point there aren't any more savings to be made.
The loop as it is should work pretty well on Ryzen when I upgrade the core system and I am able to overclock to 4.9ghz @ ddr3 2400 most of the time except for the warmest days but it looks like it will probably cost around £100 to get the extra 100-200mhz overclock on the fx 4350 so it's not worth trying anything more than the cheap shot of the larger rez. and fan.