hmmm... when i was younger..... I neglected my gf becoz of this hobby. Remembered that once I had her waiting for me for 3 - 4hrs while I rescape the rocks...... thinking back, that was not right.
But i guess in younger days, guys tend to get obsessed easier. Just remember that it is not because he place the tank above you. It is just a passion and it is good to have a healthy hobby.
Better than gambling etc. The balance in maintaining the amount of time on the tank and spending with you will come.. take a little time. In the meanwhile, just be patient. My advise is to read up more about reefing too and enjoy the hobby with him. I think that is impt for a relationship to develope - to have common interest. but at the same time, do communicate with him your feelings, being feeling neglected etc - tell in a gentle tone - most guys will understand. Pls do not use a "reprimanding" tone. Learn how to get through this stage of communication cause you will need it alot after marriage - there will be things like gaming, billards, personal time, soccer, looking after babies...... just take it postively as a trial and enjoy the hobby and relationship together..... cheers!