There comes a time in all aquarists lives when inevitably we must leave our fish tanks for an extended period of time. Although many aquarists dread leaving because of the potential disasters while away, a few simple preparation days can set your mind at ease and ensure your fish will be happy and healthy when you arrive back home.
Modify Feeding Schedule
First, you're going to want to start feeding less frequently and overall feeding less per feeding. About one week before your scheduled departure date you'll need to start feeding lightly, once a day for 3 days. After these 3 days, feed once every other day until you leave. This will get your fish accustomed to their new feeding schedule and also help cut down on potential nitrates.
The last thing you want to happen while you are on vacation is for a filter to break down or have a clogged filter create a problem. So, a week before your departure you'll want to perform a round of filter maintenance. At this time you are only going to clean half of your filter cartridges, media and filter housings. Performing filter maintenance should only be done with old tank water as tap water will kill off your beneficial bacteria. (The other half of your filters will be cleaned the day before leaving home.)
While doing filter maintenance it is good practice to only do half of your maintenance at any given time, this allows room for error, if some reason you kill off half of your beneficial bacteria, you will still have your other half.
The day before leaving for vacation, you're going to want to do a massive water change, through gravel vacuum and a good scrub of all the walls and decor in the tank. When doing your water change I suggest doing a 75 percent change, refilling with dechlorinated water, then doing another 50 percent water change and then once again refilling with dechlorinated water. This may seem like overkill, but this will get your nitrates as close to zero as you can get them.
Once your tank is filled and your fish are swimming around happily your going to want to invest in a timer. Timers can be bought for $5 on up to $100. Timers are a great way to ensure the lights aren't kept on at all times, promoting algae growth. While gone you should only leave your lights on for 3 or so hours a day. Lights are generally for viewing pleasure so don't worry the minimal lighting will not have any ill effects on your fish. If you deceide not to buy a timer, leaving the lights completly off would be the next best thing. Never leave you lights on 24 hours a day, you will come home to a algae ridden fish tank.
The next step is going to depend on the length of time you will be gone:
1-4 days: Given you have healthy fish; you will be fine leaving your fish alone without feeding.
4+ days: You should begin looking for a trusted friend. Once you have found this person, its time to portion out the food for your time away, remember to make this on the light side as you want to keep optimal water conditions for as long as possible (Dixie Cups or ziplock baggies labeled with the feeding day works great for holding food portions). Have your friend feed every other day after the initial 4 days.
12+ days: It is now time to show that trusted friend how do a small water change. Show him/her how to do a 30 percent change and how to measure out the correct amount of dechlorinator for the water being put back in during refill. It would also be a great idea to show your friend how to prime any canister filters or hang on back filters at this time. With the light feeding and a 30 percent water change your fish will be fine for up to 2 ½ weeks.
Every parent thinks their kids will be good while they are gone. I'm here to inform you, you're wrong. A party is going to happen before you get back. Inform your subadults that beer does not belong in the tanks, fish do not like alcohol, and any party that results in the death of your fish may have a similar outcome on them.
Joking aside, I cannot identify how often a teenage party has wiped out a tank by some drunk punk thinking it would be cool to pour a beer or two into the aquarium. I'm even aware of one instance where someone attempted to fry up the fish in a pan.
Once you return from vacation and find your fish sober and begging for food, you'll need to do another large water change (again I recommend a 75 percent water change, refill, another 50 percent water change, and refill), thourough gravel vacuum and filter maintenance on your last ½ of your media and cartridges. At this point your tank should be clean and ready for your departure.
I have used this method on countless business trips and vacations and have been extremely pleased with the results. At times I have been gone for 30+ days with no ill effects. With planning, leaving home doesn't have to be the nightmare that most aquarists believe it to be.
This method is used on mature healthy fish and is not recommended while medicating or on tanks that are heavily stocked.
A trusted friend is hard to come by, leave them a pizza in the freezer for all their help.
BEST OF LUCK AND ENJOY YOUR TIME AWAY!!!!!