I installed the float valve when I first installed my system, but because of the top/side bar of the tank cage being quite wide, and having to cut the holes for the valve right under it, the float valve doesn't allow filling the tank all the way to the top.
Now I was wondering how I could change that, maybe add a bit of stick on lead to the float? So it doesn't close until the water is completely up to the top. I was thinking that could be done, but you need to be very precise with how much weight you put on it I guess.
Can't find the float valve I have online, but it's the one where you can fit a booster pump cut off switch on.