Earlier problems had forced a 48-hour delay to the planned opening, which eventually took place last Saturday.
The indoor attraction, on the site of the former Atlantis water park, was built only after Scarborough Council agreed to lend the developers £9m, a move passed by just a single vote.
The latest problems today were announced in a Facebook post reading: “We are unfortunately experiencing a few technical issues with our slides.
“Rest assured they are being worked right now and will be up and running as soon as possible. Until they are fully operational again we are offering a 50 per cent discount to all our guests.
“Please accept our sincere apologies for this disruption. We hope to have the teething issues sorted out very soon.”
A further announcement later in the day said the slides were back in action.
Alpamare has four giant slides, said to be the longest and fastest in the UK and a match for rival attractions in Florida and Dubai. Together they are capable of carrying 2,500 people an hour.
There is also an indoor tidal pool that erupts with meter-high waves every 30 minutes.
The park is expected to attract more than half a million visitors a year, and has created around 100 new jobs. A “European-style wellness spa” is due to open next door, early next year.