Hi Sonnich - Well it sounds as if your pond is similar to mine - a bit murky, I lose sight of the sub as soon as it goes under water and I also use the aerial and mast to sight with. When the sun shines again it's possible to see into our pond to a depth of around a metre - that's as deep as the pond is. You seem to have got yours trimmed very well if you can stay level under water with hands off - I'm hoping mine improves with the extra stern weight. I never did get around to buying the stock battery - I made a wire cradle from a coathanger and I just use a 'Titan' Sealed lead-Acid battery of 6v 4Ah. My ESC is a Hitec EZX-R - I think they were designed for cars - the ESC will not switch on unless the throttle stick on th TX is in neutral as a safetly feature. I practiced in the pond yesterday for around an hour with no apparent loss of power - apart from, as I said in my last post, a collection of weed around the prop which slowed things down a bit. At one point I did an accidental nose dive and ploughed through a thick weed patch on the bottom - when the sub came up it had weed tangled on the front planes and it was draped over the nose cone and also the prop was heavily tangled - but at least the sub came up thank goodness - saved me paddling. I think you're very lucky getting a fully watertight seal - but at least a smear of Vaseline grease on the gasket keeps my water out. If you remember I stripped the thread on my front fastening bolt and I replaced it with a bigger sized one and use a wing nut to tighten up with - it just means undoing the top fron nose cone to do this, but I only have to do it once when getting the boat ready and once when I come home and want the battery out. I thought about going to the pond again today but the temperature outside is only 6 and there's a really cold wind blowing so I'll wait for a better day. I just wonder how you have set your front dive planes - mine are just tilted slightly forward then only go level when the mast tilts back - If my stern is a bit low I might try angling the front planes a bit lower on my next test.