A bad or old light cord. Water or moisture getting into the light can. I hope you have a GFCI on the system. Call a professional pool tech to troubleshoot and advise. A replacement may be in order.
It would cause excessive mud and the swimming pool would sink slightly. It would only cause a sinkhole if there was a hole underground under the pool.
Algae
Faulty wiring.
my pool did get milky but cleared up after 48 hours
If you are referring to a commercial pool you would have to check with your local pool inspector. The rule of thumb for commercial pools is: is you have a light in the pool it needs to work. If you don't have a light you are likely grandfathered in without a light.
That would depend on the type of light, the wattage, the shape of the pool and the size of the pool.
Lightning
The most likely cause is hydrostatic pressure from underground water. This can be a very dangerous problem for the pool and I would contact the installer immediately for an onsite consultation. If it is hydrostatic pressure and is not relieved, the pool can be permanently damaged. thepoolandspawarehouse.com
Bubbles in a pool can form due to air getting trapped in the water circulation system, a leak in the pool plumbing, or a malfunctioning pool pump or filter.
yes you can but with water and electric you should have someone that is insured do the switch it would be much safer
Yes.. If the lite ring or facering are corroded the chemical ballance has been way off..
You need the proper tools and the qualifications to do this job. Call a qualified swimming pool electrician or pool tech to do the job to code and install a GFCI. k