SP mk16/18 vs mk25af?..or Apeks

[rodcoleman]

I am in the market for a new reg and would like to buy SP because it is easy to get serviced anywhere and performs well. However, I will dive in cold fresh water (40f) and air temp (10f) and am worried about the cold water performance.

I would prefer to go with a mk25 however, perhaps a diaphragm reg (mk16/18) would be a better choice? Can any tell me about the difference in cold water performance between the mk25 and mk16/18? also, the perceived ease of breathing?

Would Apecks be a better choice, even if it is harder to get serviced and breathes a little more wet than SP?

Thanks for the input.

 

[kavka]

I have MK25/S550 and MK16/r190 for backup. I'm I use MK25 all the time. Never ha any problem even in watter 1 deg. C, air was about -10.

 

[docmartin]

here is what i have found researching the issue: UK's diver magazine tested the mk25 in cold fresh water with no problems. i also read a french test of a number of cold water regs. in this test they timed how long it took for the 1st and 2nd stages to freeze when being purged in very cold water (i forgot the temp). the apeks and sp mk25 performed equally well (50sec until they iced up). the sp550 and 600 2nds did better than the apeks (tx 50 i think). however, this was a lab tests not real worldn and the apeks 2nd performed well, too.
when you look at scubaboard you'll find that some people have had problems with the sp mk25. i have found noone reporting problems with apeks. therefore, given the freeze issue it seems to me that apeks is the safer bet although sp seems to be fine by and large. if it were not for those nagging exceptions...
on the plus side sp seems to breathe a little easier and definitely is more widely available and serviced. however, if you want to do your own reg service it seems like apeks parts kits are easier to get than scubapro when you order through european sources.

 

[ElectricZombie]

If I were doing a lot of cold water diving, I would probably go with an Mk16 since it is sealed. You can't tell any difference between an Mk25, Mk18 or Mk16 in terms of breathing. Also, the Mk16 does not have a swivel...ones less part that you don't really need.

 

[MPHS]

When you plan for ice-diving I would suggest Apeks ATX 100 or the ATX 200, I am diving in Holland at all weather conditions and if you want to go for safe diving the Apeks is the answer. I own my apeks ATX200 for about a year now and have made 3 ice-divings with it and I can not complain.

good luck with you decision buying SP or Apeks

MPHS

 

[realdiver7]

Speaking of the sealed SP MK16, does anyone know if the MK18 is also sealed, even though it has a swivel turret?

Thanks.

 

[oxyhacker]

The SP Mk14, 16 and 18 are all sealed only in the way that any diaphragm 1st can be said to be sealed, in that the diaphragm keeps water out of the inside of the stage - this isn't a special feature, it's just the way they all diaphragm 1sts are made.

Some of the competing regs, like many Apeks and AL Legend models, have a second diaphragm to increase cold protection. SP does not offer this.

Speaking of the sealed SP MK16, does anyone know if the MK18 is also sealed, even though it has a swivel turret?

Thanks.

 

[ppo2_diver]

My first reg was a SP MK18UL. A great overall reg, but I had a problem with freeflows during ice dives. I moved to an Apeks ATX50 and I can't tell the difference. This will be the first winter I get to use it for ice diving. I'm expecting it to preform better than my SP.

 

[mempilot]

My 2 Apeks DS4's are sealed. Apeks makes different 1st's that are mated up with just about any Apeks 2nd. Just depends how you order them. You can get the DST or DS4 with the ATX and TX 2nds with one exception. The ATX200 comes with it's own 1st. I'm diggn' the DS4's performance.

 

[aquaoren]

Rescuediver009 reported once that his Apeks froze on him during an ice dive (It started freeflowing, which can indicate freezing).
If You want a reg that will work everywhere regardless how cold-Buy a Poseidon