Okay, so usually I vacuum gravel/
water change every couple of weeks on my established tanks, however my parents are redoing the upstairs bathroom and therefore I have no sink to hook my Python up to (and no other sinks will fit it)

My question is... what is the easiest, most efficient way to do a water change? I used to just use a pale, but was wondering if there is a better way?
I just did a 50% water change on my 37 gallon on Friday? because the nitrates are out of control. I tested the water again today and brought it to be tested to double check and the
ammonia, nitrates, nitrites, etc are still very high. I added some ammonia remover and
nitrate,
nitrite,
chlorine,
chloramine remover today to hopefully help. How do I get those under control? More water changes until it is better? Usually it's fine, but without a sink, I hadn't been able to do a WC in a couple months and everything got really high.
How much water should I remove on my tanks and how often should I remove it? How much water and how often should I remove it on my tanks where the nitrates, etc are very high?
Thank you.