Getting the best from the Brewzilla 3.1 (35l) ?????

Hi again All,
I brewed again yesterday, and decided to make the Belgian Pale (the Kölsch will have to wait until after Christmas) . . . . . . and I had a much better brew day than any of my previous attemps with the "beast". It wasn't perfect, but the flow/recirculation and the sparge were noticeably better.
I had a grain bill of 5kg of which 3kg was precrushed Pils malt (bought before I got the mill, so needed to be used), and 2kg of Maris Otter that I crushed myself. I reset the mill gap to 1.2mm, and moistened the whole grain with a fine spray. I left it ~10 min before milling. I chose the 1.2mm gap because I felt that the 1.45mm suggested in the Gladfield article was just a bit too wide for my Maris Otter. The crush looked pretty good, and was almost dust free. I also decided to use 150g of rice hulls because the precrushed Pils malt seemed to be quite fine and was dusty. I rinsed this with hot water, and let it drain before mixing it in with the rest of the grain.
I mashed in with 18l of water, and let it stand for 5 to 10 min before turning on the pump (as recommended by Gash and Cherry1). The circulation was a bit slow to start with, but seemed to settle down to a steady flow after a short time. I was able to set the ball valve to ~1/3 open. I would have liked to have had a higher flow rate because I was fighting to keep the mash temperature to the set value because of the low ambient temperature (a very cold garage at the beginning of an English winter). However, I ramped up the set value a couple of degrees, and it was more or less OK after that.
The result was a wort with an OG of 1.051. Based on the predicted values this suggests an efficiency of ~70%. I usually get ~75% with my old mash tum and sparge system, but I'm OK with this.
The next brew will be based entirely on home crushed malt. I'm not sure yet whether or not I'll try it without the rice hulls using the 1.2mm gap, or reduce the gap to ~1.0mm, and continue using rice hulls???? I'll mull it over tonight with a pint or two.
Cheers
Geoff

good Stuff as finnroo said only change 1 thing at a time

my thoughts with 5kg of grain i would be looking at least 21l of h2o to mash in

ricehulls may give you less effiency but will help not getting a stuck mash or sparge as the rice hulls act like filter

70-75% effiency is good in my book

have fun

Thanks for the encouragement and words of wisdom.
I had never used, nor needed to use rice hulls in anything I brewed before buying the Brewzilla (including many batches of Weizen over the years). Your comments on the possible reduction in efficiency are interesting. My primary goal at the moment is to get to a point where I have a good circulation through the mash, without sacrificing too much efficiency. If I can achieve this through step by step adjustments to the mill/grain crush, then I'll be happy not to use the rice hulls at all.
More mash water is also worth considering . . . . but I'm a bit concerned about reducing the sparge volume too much. Or is that not a problem with a recirculating system?
Cheers
Geoff

Thanks again to both of you.
My old mash tun was based on two 30l, large diameter PP pales with lots of foam insulation (one inside the other, with 2mm holes drilled into the bottom of the inner pale, and a tap in the outer one for drainage). And as you point out from your experiences using an insulated cooler box (or as you call it in Australia "an esky"), the grain bed was not that deep compared with the diameter. I realised that the deeper grain bed in the Brewzilla malt pipe is probably causing it to compact more. The result being that the flow through the grist is slower. I'm in no doubt now that the rice hulls help a lot, but equally (based on everything that I've learnt from this forum) the crush has got to be right too . . . . . So, I will persevere.
Just for the record, I already mash for ~90 minutes (old habits die hard), but I have never bothered to mash out. It never seemed worth the effort, particularly with my old set-up. However, it will be easier with the Brewzilla, so I might give it a try. What temperature do you normally use? I already sparge at ~75degC.
I'm learning a lot from you guys. You are very lucky to have such an enthusiastic and helpful home brewing community in Australia. Unfortunately there isn't anything like The Home Brew Network in the UK. Our local brew club is very sociable, and a great place to compare brews, have a chat, and occasionally get pi55ed. But we havn't had a meeting since February because of social distancing and pubs closing etc. So its really good to pick your collective brains

Thanks gash

Honestly I haven’t but I bought a few kits online and pretty much stuck to one place for the last 1/2 dozen brews and each time told them I’m using a brewzila and they just say should be fine. I’ll try the rice hulls for sure. I thought I was onto it once I’d got rid of that fine screen. I also did a cream ale and that was the worst maybe because of all the adjuncts in it? The best flowing ones I’ve had were a pacific ale from G&G and 2 mild ales one I got online and one I picked up from beerco but I’ve had others from those places and it’s been stuck sparge central lol. I’ll get it right I might buy a mill and try that any recommendations on mills?
Cheers
Ray

Have posted a recommendation under the topic "Grain Mill"
Cheers
Geoff