Welcome my padawan!!
I will teach you a couple lessons here!!!
So you want to be a clam addict!!! You've found the right place..
1).What and how much lighting do clams need? The tank in question is a 35 G bowfront with 175 watt 5500K halide bulb and 2 32 watt Ultra-Actinic compact fluorescent bulbs.
That lighting is O.K. It can be better.. I'd suggest picking up a 250w... With that 5500k you'll have some nice growth!! But that color to many is ucky! AS for what you can keep in that tank?
Hippopus (get's very large)
Maxima (higher in the tank)
Possibly a crocea, if you put it WAY up at the top of the tank.. These are the smallest of the tridacna species, and the MOST light demanding.....
Of course what I noted as large, takes many years to grow large enough for it to become a problem... I'd stay away from a gigas or hippopus for they get quite the humongoid in a short amount of time....
2). Will a coral banded shrimp be a problem?
I do not beleive so, I have one in my 29, and it leaves my clams in harmony... However each creature has it's own tastes and mind, so I'd just observe him if he does anything... Of course I'm not making any guarantees, but I'm sure he will leave them alone.
3). What to look for when picking out a specimen?
You should look for a piece larger than 3 inches (mantle to mantle which is the colorful extendy part
) Look for a clam that is opened up well meaning that the shell is opened, the mantle is extended over the edges so that you cannot see any edges of the shell.... Be sure to look under the mantle to check for any pyranid snails which harm the clam to certain degrees, DEATH. Use good judgement.. Look for colorful pieces...You can tell if a clam is healthy or not... It's simple logic..... I'd suggest shooting up Barry at clamsdirect.com or anthony at aquadesignz.com and they will more than happily help you pick out a healthy first clam.... Tell them that Elvis sent you and they'll give you free clams!!!!
4). What substrate is need/ preferred? Tanks has 2 in of crushed shells/coral.
That's no problem at all, although I'd really ditch that whole Idea and go with a live sand substrate.. It will help you with much hassle..... You can keep a squamosa and derasa in that substrate... But a maxima or crocea would need to be placed high in the tank with your current lighting....
NOW... Keeping a clam is a beautiful thing, but it's not all fun and games.. Clams need their supply as anything else in the reef aquaria does... Meaning that you will need to keep regular tank maintenance up.... Ammonia 0, nitrite 0, and Nitrate can be a max IMO and IME 15 ppm... Clams like some amounts of nitrates..Which I don't want to get into a whole discussion about..... I've had many fellow reefers keep clams in tanks with even 20 ppm Nitrate....
Clams need calcium to grow!! You should do regular dosing's Kalkwasser or B-ionic ( or even both! Hieuh!
).. But to save you hassle, a calcium reactor would be the best choice!! Do a search on kalkwasser dosing and you'll find how to do it.
I wouldn't keep clams without skimming, It's just my preference, and will save you a hassle.... Clams need clean healthy water... Not polluted dirty water
Anything else I forgot guys???? That's about all I can think of now....
Again, I'd strongly reccomend you buy a book on clams, or read around this forum about them before purchasing one......
How old is the tank?? I wouldn't add a clam to any tank younger than 6 months... at 6 months an aquarium is mature enough to an extent where it is stable... levels (ammonia, nitirite etc.) aren't flunctuating around which is lethal for the clam.... Be sure to keep your Ph between 8.0 and 8.3, temp anywhere from 76 to 82.
Good luck my padawan, and may the force be with you!:strooper: