At the advice of some well respected telescope breeders I've recently removed any air strips and air wands that I previously used and have changed to exclusively using the large Hagen Elite bubble disks in my three telescope tanks. The air strips were creating entirely too much current and were actually creating additional stress to my telescopes by fighting excessive water movement. Second, by using these disks I've eliminated any possible sharp edges which is a potential hazard of eye injuries and cuts/scrapes which can lead to possible bacterial infections. The rounded edges will eliminate any such hazards.
I've seen many complaints and have experienced the frustration myself of how to get these bubble disks to stay flat on the bottom of the tank. I've worked with these for a while and have come up with an easy way to get the disks to stay flat on the bottom. I power mine using Whisper 60 pumps which perform quietly and provide all the necessary air pressure that you need.
1. Most importantly, after removing the bubble disk from the packaging place the disk on the bottom of your tank and let it soak for a 12 hour period. This will condition the air stone and help remove air from the stone.
2. Use flexible standard airline tubing. Don't use the semi-rigid type of tubing as you'll need as much flexibility as possible.
3. Before setup of the disk, be sure to install a check valve within the airline to protect your air pump from water back flow.
4. Use 3 to 4 of the airline suction cups to secure the airline into place either to the side or the rear of the aquarium. Slide these over the airline before attaching the bubble disk to the end of the airline going into the tank.
5. Start by forcing the tubing tightly onto the connector of the bubble disk. The connector flange is slightly larger than the tubing itself so force will be necessary to get the tubing over the flange and will offer a tight fit without any gaps.
6. Work the disk into the airline and twist gently to position the disk level on the bottom of the tank.
7. Position and attach the airline suction cups in place along the inside of the tank in order to keep the airline tight against the edge of the tank. Keeping it tight against the sides will eliminate the possibility of of a fish becoming trapped within it.
8. When running a smaller tank such as a 29-30 gallon, I've found it necessary to also add an adjustable flow valve to keep a comfortable flow of air into the tank without creating undue stress. Larger tanks of 40 gallons plus shouldn't need a flow valve installed.
I've attached a video of all 3 of my telescope tanks that each have the large bubble disks in place to give you an idea of disk and suction cup placement. Again, the most important factor to get these to stay in place is to condition the disk by soaking in your tank for at least a 12 hour period. The airline suction cups will then assist in holding the disk down and keep it from moving or floating. I keep one large disk positioned at one front corner of each tank. Each one provides more than enough aeration and surface agitation to keep my telescopes healthy. Hope this helps!