What HOT5 Lights for Clam Tank?

[Mentat]

FOWLRs are doing good so plan to set-up next a clam tank for a couple of the smaller Tridacnids. Have 2 tanks available for project, a 30 gal. breeder or a 40 gal. breeder. 30 will have a water column height of around 10 in. while 40 have 13 in. Trying to decide which tank to use if light system will be a tank lenght (36 in.) HOT5 with either 4 or 6 tubes.

1. Is a 4 tube unit (i.e. Current's Nova Extreme 4 tube 156 watt unit enough for a 10 in. depth? How about 13 in.?

2. If not, same question for a 6 tube unit (i.e. Current's Nova Extreme Pro 6 tube 234 watt unit?

If you have other recommendations IRT lightning (systems or lamps) for either of these 2 tanks please advise.

 

[a4twenty]

generally the 6 bulb fixture is for and 18" wide tank and a 4 bulb for a 12" wide tank. the smaller tridacnids are light lovers so i would suggest the 6 bulb fixture, and it will be off more use later if you decide to upgrade.

 

[Mentat]

Thank you A4twenty, will go with 40 gal. (it's 18 in. wide) and 6 tube light.