Timer not working..

[Flupke]

Hello,

I have a bit of a problem.
I recently set up a new planted aquarium. It's 72g, and lit by 4x39W lamps. Plants include a whole lot of java ferns, quite a few bushes of cabomba, java moss, some grasses, and a couple of anubias.

I'm off on business tomorrow morning (Tuesday morning), and won't return until Thursday evening. Normally, that wouldn't be a problem.. except the timer I bought appears to be faulty.

So, now the question is, do I:
(1) Leave the lights off from now (Monday night) until Thursday evening?
(2) Leave 2 out of 4 tubes on for the entire period?
(3) Leave all 4 tubes on (seems like the least desirable option to me)?

I don't have any fish yet, as it's still cycling. It's midnight now, and my plane is leaving quite early in the morning, so no options for buying a new timer.

Thanks

[Jaykit]

There is no fish so I would say that you either the 1st of 2nd metioned options. I'm sure that most people would recommend just having the lights off for the time.
(1) Plants will survive for 3 days with no light easy just as fish would if you didn't feed them for 3 days.
(2) Less intense photo period, but as long as there is nutrients in the water the plants will keep doing their thing.
(3) Full intesne photo period same as the 2 bulbs but you might notice that you will have melting on your java ferns and maybe some other of the plants because of the intense long photo period.

[coach_z]

keep them off....less problems will be created this way

[jpappy789]

Leaving them off is much better than leaving them on 24/7. Your plants should be able to recover after three days.

[Flupke]

Thanks all!
I'll leave them off.

I'm a tiny bit worried about the Cabomba going all sad on me when light-deprived, but.. life isn't perfect.

[jpappy789]

Thats the plant that will probably suffer most.

[Flupke]

So... I'm only getting back home at about 10pm on Thursday. Should I turn the lights on and leave them on for a while, or leave the plants in the dark for even longer and just resume the normal day/night cycle from Friday morning? They'll be pretty low on carbs after three days of not photosynthesising, and could do with a bit of an artificial day at night. On the other hand, I'd have to then induce darkness during part of the following day to avoid a ridiculously long photoperiod. So it's bound to get a bit.. complicated.

Thoughts appreciated.

[coach_z]

i see no problem in turning on the lights for a few hours once you get home...turn them on when you arrive home turn them off b4 bed.

the following day resume your normal schedule...no need to fuss about time persiods

[Flupke]

Thanks for the feedback, everyone - much appreciated.

I've just returned, and the damage appears to be limited. At first glance, the Cabomba is looking perfectly healthy, and so are most of the other plants. The grasses in the foreground (no idea of the genus) are looking a tad brownish, but not completely gone.

[coach_z]

do a PWC, dose some ferts (if you dose ferts), and then give it 48 hours and it will be fine.