What causes daily minor die-off?

I use the word "minor" loosely because I started off with 1200 Ocellaris larvae and have much, much less now.  However, there hasn't been a day where I saw a more significant die-off than other days other than one day when I had an ammonia spike (1200 babies requires a lot of ClorAm-X).  This daily die-off is annoying though, I only siphon out 10-20 every evening, but obviously many more are dying (they are almost 2 weeks now).  Now, this problem isn't specific to this batch of Clowns.  This is something I have struggled with for all the batches and species so far.
 
Here is what I do, let me know if there are details missing...
 
Hatch night I collect the tile, scrub it down (over the sink) everywhere there aren't eggs.  Soak eggs in 1 liter of new ASW with 1-5 mL hydrogen peroxide (I've seen no difference in the amount, so I'm currently doing 5 mL) for 15 minutes, sometimes 30 minutes.  Time doesn't seem to matter as far as initial hatch goes.  The tile usually goes into the larvae tank (5-10 gallon tanks) that has been up and running with new ASW with 1 mL bleach per gallon for 12-24 hours, then dechlorinated for about 1 hour before eggs are introduced.  I have checked chlorination to be sure I am adding enough thio. SG 1.020 and temp 80F (same as broodstock).  I have tried using micron filtered broodstock water and have had total loss on the 3 occasions I have tried.  I have messed around with aeration and find no difference with light aeration or heavy aeration.
 
Next morning I add rotifers and RGreen Omega.  I add few enough rotifers that the larvae clear the tank about 95% by light out in the evening.  I add about 1 mL RG Omega per 10 gallons.  The morning after that I add maybe 0.5 mL RG Omega per 10 gallons to maintain greenwater, and add fresh rotifers.  I continue this.  Lighting is 7.5 watt incandescent bulb that shines on half the tank.  I watch the fry and if they are avoiding the light I turn it away a bit more.
 
On day 3 I start adding a very small amount of TDO A a few times per day.  The evening of the 3rd day is also the first watechange.  I siphon out 50% through a coffee filter so any rotifers are removed, but larvae aren't sucked up.  I bottom siphon this day too.
 
Around day 5-7 I switch out the 7.5 watt bulb for a 13 watt spiral compact fluorescent bulb which is quite bright.  I shine it away from the tank so half is lit.  When I find most of the larvae congregate under the lighting (close to meta) I turn it more towards them.
 
On days 6-9 I find are the worst for ammonia spike, I have to be really on top of it.  Maybe this is a sign that I am losing many larvae at this point?  Meta is usually a few days behind what I have read in other peoples' reports.  Once I start seeing white bars on their heads they are eating TDO A quite well, and I start backing off the rotifers so I add just a small amount of rotifers twice per day that are usually cleared from the tank in a couple hours.  
 
After meta, I usually lose 1-3 per day until around a month old.  After a month it is unusual to lose a fry.
 
Any ideas??

Don't let fear and common sense stop you! =]

I'm very new to the world of breeding but hopefully I can offer you a different perspective.
The first portion of your process "Hatch night I collect the tile, scrub it down (over the sink) everywhere there aren't eggs.  Soak eggs in 1 liter of new ASW with 1-5 mL hydrogen peroxide (I've seen no difference in the amount, so I'm currently doing 5 mL) for 15 minutes, sometimes 30 minutes.  Time doesn't seem to matter as far as initial hatch goes.  The tile usually goes into the larvae tank (5-10 gallon tanks) that has been up and running with new ASW with 1 mL bleach per gallon for 12-24 hours, then dechlorinated for about 1 hour before eggs are introduced.  I have checked chlorination to be sure I am adding enough thio"
Sounds extremely harsh, what is the actual benefit of doing this? I would seriously consider trying a clutch without this procedure, I hope you don't take this as criticism towards your process but in my opinion, you may be overdoing it. 
 
I've also noticed that feeding TDO on day 3 will cause your tank to become toxic a lot faster, I've started to wait until day 4-5 to feed TDO and when I do, I do it in VERY small quantities.
I would also lay off the water changes a bit and use Sea Chem Prime to fight off any ammonia spikes. My first water change is usually right before meta and when I introduce new SW I do it through a drip method.
 

 
Thanks for your input. 
 
I actually do plan to skip the sterilization process of the larvae tank and just use new ASW on my next hatch.  I can't skip the process with the eggs though because there are hydroids in the broodstock tanks.  I do waterchanges the same way - I drip it in.  I use ClorAm-X for ammonia control, I just find that very suddenly I need to use much more starting around day 6 or so.  I could definitely start holding off on starting the TDO.  they really don't show a lot of interest until day 5-6, but is that because it takes them 3 days to get used to the dry food or is it because they just won't accept it that early I'm not sure.  However, I do know that some people have had a certain amount of success skipping live foods entirely and just feeding Otohime or Golden Pearls, so I'm not sure.
 
Thanks for the ideas!

Don't let fear and common sense stop you! =]

Conventional wisdom is that you either have to start out with a sterile tank, or use antibiotics a couple of times during the run.  I would not skip the sterilization.  But it is not necessary to wait so long between steps.  If you want to, you can chlorinate for an hour, and dechlorinate, test, and you are ready. What you are doing sounds entirely reasonable to me. Usually, though, I do not start giving TDO until they are nearly at meta, or after. And when I do, I give them the tiniest sprinkling until I am sure they are eating it. 
 
You have majorly large nests, if you have 1200 larvae at a time.  One can only expect that some will die off each day. Use lots of air, keep monitoring the ammonia, and doing the water changes.  
 
Do your RO water filters need changing? Particularly the carbon and sediment? I have had some problems when the filters were too old/depleted that went away once I changed them out.

check out Kathy's Clowns, llc website:
http://kathysclowns.com
Captive bred clownfish and more
(Wholesale to the trade.)

 
What antiboitics are used?  When do people start dosing them?

 
Hmm, Kathy you have me thinking here.  I haven't been using RO water.  For my broodstock I use tap water filtered with sediment and carbon filters, then add ChlorAm-X to get rid of the resulting ammonia left over from chloramines.  I use water from this same tub for my larvae (this water is not sterilized, but I think it's just initial sterilization, right?).  This works just fine for my broodstock, but maybe I need to start using RO/DI water for my larvae tanks.  I will start doing waterchanges with RO/DI saltwater.  Thanks Kathy!

Don't let fear and common sense stop you! =]

About antibiotics: I don't know since I don't use them.  I recall reading that Martin Moe used streptomycin when he started rearing orchid dotty backs, and another old time clownfish breeder used some antibiotic, but I'm not sure which one.  For clownfish he used it when setting up the larval tank, and again a few days later.  Bacteria really can do some harm, in addition to raising ammonia levels.
 
Mindy,
I just assumed that you use RO since most people do.  I never use RO, as for my city water, it seems unnecessary.  Six years later, I think I am OK without it.  So I don't want to say that lack of RO is your problem.  But your water may be different from mine, so RO might help!

check out Kathy's Clowns, llc website:
http://kathysclowns.com
Captive bred clownfish and more
(Wholesale to the trade.)

Ok, thanks for that Kathy.  I did lastnight's waterchanges with RO, and will try starting the next larvae off in RO too.  It's worth a shot.  It just means I have to set up another water mixing tub 'cuz I ain't using the pricey reef salt in the larvae tanks! 

Don't let fear and common sense stop you! =]