Re: Vacuum Head hard to move along pool bottom (other styles
Based on your photos, you can control how much or how little suction goes through your skimmer by opening and closing the two blue handled ball valves coming off the front of the pump. The valve on the left ( as you are facing the pump) says Skimmer, the one on the right says MD (Main Drain) on it. So if you are going to vac, typically you want to maximize suction to the skimmer and would close the Main Drain valve. If you think you are getting too much, you can open that valve. Are you closing the Main Drain when you vac already? In my experience with larger pumps like 2HP, closing the MD causes the pump to cavitate, and you get poor flow. Usually its a good idea to open the Main Drain half way. If you are already vaccing with both valves open, and you feel you are getting too much suction, you may have other issues. Sometimes when there is water under the liner, it will form a seal with the vac head, and be very hard to move. Do you know if there is a high water table where you are?
All that being said, I hate using those vac heads. They tend to be difficult to move. As mentioned vac heads with wheels are intended for plaster/concrete pools, but I have used them on liners for years. WARNING: If you use it on the liner, you CAN do damage if you don't know what you are doing, and you aren't careful. They can pull up the liner and actually suck a hole in it if you aren't careful. The problem is usually where the bottom bends downward at the top of the slope. They can also leave wheel marks on the liner, and if your Vermiculite base is soft underneath (It shouldn't be, but I've seen it a few times) it will leave tracks in it.
One trick that I use to improve the performance of these brush heads is to cut out some of the bristles. If you cut away 2 sections of bristles on each side of the triangle it will reduce the suction between the vac head and the floor and allow for more flow from around the head. It also makes it way easier to suck up larger things like leaves. Rather than having to lift the head to suck up a leaf, you can just push the head towards it and it will find its way into the gap. If cutting away 2 sections isn't enough, cut another. If you cut away too much you will have trouble getting enough suction, so start small and cut away more until it feels good. Start with the sections closest to the middle and work from the middle out towards the edges.