Visiting off peak is definitely a bonus, was mostly quiet but not a lot of things were open due to it being off season. Very clean, good value for money. The facilities were good and the actual water park itself was very fun and plenty for you to do. We booked a 3 hour slot on the day which was really cheap and easily done. I wouldn’t say you’d need longer than that really. Only problem we found, as two British people that were tourists and only visiting for the day with not a great deal of our usual things to take with you swimming we saw on the website you could rent towels, you could also purchase them in the shop but the lady who was in the shop didn’t speak a word of English and it was hard to justify spending over 200 PLN for 2 thin towels we weren’t going to use again. Tried to enter the sauna world only to be greeted by a very rude lady manning the desk and was very brusk with us when we didn’t understand a poster that was all in polish. I didn’t have my phone with me to try and translate as we were in a swimming pool area, and she said we had to pay for a towel, we couldn’t rent. Which is not what the website or this poster said when she frustratingly flipped it round when we didn’t understand. For whatever reason, you can’t rent only buy. Think this needs to be clearly stated if it’s not allowed anymore. Signage was pretty clear and if there wasn’t an English translation we could usually figure it out by the pictures but some weren’t so we just had to guess as a lot of the life guards also gave us very blank looks when we spoke broken English to them. It does seem like a very nice local leisure facility but was expecting perhaps a bit clearer guidelines regarding the towel situation. We had to air dry ourselves when getting changed which wasn’t the most comfortable experience. Annoyed we didn’t bring towels from the hotel now but just thought it would be fine as per the website!