For submitting a story on your happiest day (or one of your happiest days) for the anthology titled "Ecstasy" there is no length requirement. I anticipate since we are generally talking about describing about 12-24 hours, there would probably be a common average length. But some people may be able to better sum of the experience than others. Some, like me, might include flashbacks to other times that affected the day in question which would then cause it to be longer.
I doubt any of you would churn out 50 pages writing on your happiest day.
I had not anticipated poetry, but if some one had a poem that seems to accurately capture the essence of one of your happiest days, and it is good, we could probably include it. But it should still fit the "happiest day" focus, not just be on happiness, or ecstasy. Of course, if it is really great, we might try to use it no matter how little it meets the guidelines. That is the way with quality, it rights its own rules.
A human life, or a day in a life, can be seen as a wave with peaks and dips representing how important the events are that are taking place, from your subjective viewpoint. Sitting on the crapper, brushing your teeth, feeding the cat, etc., are usually dips rather than peaks. People are interested in other people's peaks -- both what they are and (what I think some writer's neglect) why the writer views them as the peaks.
Your memory keeps a record of this life-wave by selectivity. What you remember best is, ergo, what you perceive as a significant peak (or a significant dip). Those things that cluster in the middle, low peaks, low dips, are not as easily recalled. They make less impression. And they are generally worthless as writing material.
If you go through any span or your life -- from a day to a decade -- and ask, "What were the most important events during this time of my life?" your memories will answer you. Perhaps the answer will surprise you. Or make you ashamed. But it is essential you give the answer honestly, without embellishment to make yourself look good, or gloss over your own flaws. And figure out for yourself why those memories were so important to you. It will probably be because they shaped how you view life, love, etc. Perhaps some lesson of life. Even if you think the lesson is vacuous, like if your happiest day was your first roll, which was when you learned that what really matters for being happy is not the people you are with, or the music you are listening too, but the quality of the drugs you are on. If you believe that, if that is the lesson you learned for yourself from your memories, don't be ashamed to admit it. If you are being honest, other people will identify with it however petty or selfish or counterintuitive or embarrasing it may seem.
Anyway, go through the significant peaks and troughs that surround the relevant topic (your happiest day) in your own words, with your own style, and also make your story express to the reader not just what happened, but why it made you so happy. The why is as important as the what.
~psychoblast~
