Order new steps from your local pool supplier or from the web. Examples:
There are a number of things you could use to repair a crack in the plastic steps in your pool. You could use pool putty for example.
There are a number of ways you could repair a chip in a plastic in-ground pool. You could fill it with a plastic that hardens when it dries for example.
Replacing vinyl liner pool steps is costly and unnecessary. These steps are fiberglass and can last 60 or more years, if cared for properly. But you must replace the white coating, swimming pool gel coat, once every 20 years. Even after the 20 years, the steps can still be repaired or refinished by any DIY pool owner. SwimmingPoolResurfacing.com has the products and the help you need to restore worn or torn fiberglass (plastic) steps.
could be mustard algae buy some chemys
Some pool companys are not in business. most all inground pools have the same size treads..
Scale, from high calcium hardness in your pool water
Recommend purchasing a shop repair manual fir that vehicle if you want to DIY.
AnswerDrain the water out to the point where the steps needing repair are no longer under water. You will need to re-plaster them, let is cure (and dry) then refill the pool. The easiest way to repair a leak in pool steps is with a two part epoxy. This is readily available at your local pool supply store. First identify where the leak is. Than enlarge the hole with a screw driver. Mix only enough epoxy to do the repair and push the mixture into the hole and smooth it out. You do not have to drain the pool to do this. The above assumes that this is a concrete pool or an inground liner pool with fiber glass steps.
Those $13.00 repair manuals found at Autozone will cover that very good. They usually pay for themselves on two repair job. IF you have the tools.
Document activities and outcomes of repair steps
it is very hard to do, and too many steps to put on here, but you can go to autozone or kragens and get a haynes repair manual for $15. The repair manual has step by step on how too with illustrations