Vacation And The Planted Tank - What's Your Strategy?

[FoundMoney]

I've had a 30 gallon planted tank running for many years but it has been moved, replanted and otherwise disrupted a couple of times in the last 2 years.  I have 2 earth eater cichlids (I believe Juripari Santoperca but not 100%) sure and between their activity and the moving of my tank, I had a crash earlier in the year and removed all my plants except for a lonely crypt that was still holding on for dear life.
 
About 3 months ago I decided to start over again and replanted the tank with ludwigia repens, cabomba, and vallisneria. About 2 months ago I also added a Fluval 88g CO2 system and have seen pretty good growth in all of the plants, although it has been a balancing act between, proper nutrients, light (2 x 39W T5HO), CO2, in order to get good growth and minimize algae.  I am also using Total Substrate root tabs in the substrate and add small doses of micro and macro nutrients every other day.  I've been adjusting the amounts by observing both plant and algae growth.
 
Rather stupidly however, last week I added some Glossostigma to the tank hoping to add a nice carpet to the foreground.  It's only been 5 days but I think it's starting to take hold as I'm already seeing some vertical growth and new leaves popping out of the substrate.  I say stupidly however, because I will be going on vacation for a week and won't be able to monitor tank conditions and adjust parameters as needed.  I should have waited until my return to plant the Glossso.
 
Today is Thursday and I'm leaving on Saturday.  My plan is to run the tank as a "low tech" set up while I'm away.  Tonight I will do my weekly water change and usual fertilizer dosing.  I'll also clean the filter to minimize the chance of a filter back up or malfunction.  I will let the tank run as it normally would, but on Saturday morning before I leave I'm going to reduce the photoperiod from 10 hours to 5 hours and will turn off the CO2.  My hope is that the plant growth will slow with less light and no injected CO2 and that there will be enough nutrients in the tank to keep the algae at bay.  As far as feeding the fish goes, I'm thinking I can feed them Saturday morning before I go and then again when I return next Saturday night.  Sometimes when I've gone away I've asked someone to feed the fish but I think I'd be better off letting them go hungry than risk overfeeding, which has happened in the past.
 
So what do you think of this strategy and what do you do when you away from your tank for a week?

 

[Mamashack]

From what I've read any light triggers the plants to commence photosynthesis and if they are used to having CO2 injected they could be shocked by its sudden withdrawal.
I don't keep a high tech tank, but have been following discussions on here and that is what I have gleaned.
Is it possible to have a zero electric photoperiod since they will get some ambient light from the room they are in (unless it's underground!)

 

[FoundMoney]

Shutting the light off completely is an idea.  However, I'm now thinking that it would be better to keep a little CO2 going while lowering the photo period.  There would still be nutrients for the plants but the available light would be limited, hopefully keeping them relatively healthy, while not allowing algae to get too bad.

 

[DrRob]

I'm guessing you'll miss this reply. I'm a bit slow about picking up topics as things are crazy at work and I'm setting up a new computer.
 
There are two real options, as you've had pointed out you can go low tech. Personally I'd just turn the lights off.
 
The other option is to run the high tech regardless, put the ferts in all at the beginning of the week and walk away. Generally, unless you have very sensitive stock, that approach is fine.
 
The final answer, which probably isn't an option at short notice, is to automate. I have peristaltic pumps running the fertiliser mix, a solenoid on the CO2 and the lights on a timer. Mainly because I work shifts so can't be reliable for timings of things, but it makes vacations easy.

 

[FoundMoney]

As a follow up, I basically went low tech.  I day before I left I did a water change, cleaned the filter and added some trace nutrients.  I turned off the CO2 and set the lights at 5 hours.  I came back to an algae free tank.  The ludwidgia looked great.  Vals looked unchanged.  Cabomba became overgrown.  The glasso was basically non-existent.  The fish buried some and uprooted the rest.  The buried pieces melted and rotted, but there were a few viable pieces still floating around.  Between the lack of light and CO2, overshadowing but the cabomba, and over active fish, the glosso didn't really stand a chance.  I'll see if what's left can catch on.  Otherwise I'll have to start over.  However, all in all, I'm happy with the outcome.