Best 250W DE Bulb?

[SpokaneReef]

I have been all over Sanjay's site and from what I can gather the XM 10K 250W DE is the best as far as PAR.

I use a M80 Ballast by Hamilton Tech but it is not listed in the options.

I am going to shoot for growth so I can get the frags to encrust a little faster so the 20K bulbs go on the shelf for awhile.

Anyone know (with facts) of a better bulb for growth that is DE 10K?

From what I gather from Sanjays site the XM bulb is 95 to 136 after the shield, and depending on the ballast.


Thanks

[charlie]

EVC DE 10K--PPFD 147
SUN AQUATICS DE 10K-- PPFD 116

I kind of gather that the HQI is about the same thing as the M80 ballast, why would he have the M80 in parenthesis ????

One word here, how many times have you changed bulbs around since this thing got going? You have to stabilize and give your corals time to adjust James, stop changing stuff around in the tank. Every time you change something, flow, lighting, the coral has to adjust, and that is why you are not getting any noticeable growth. BE PATIENT for gosh sakes and you will be rewarded, no matter what bulb you throw on there. Things don't happen overnight, like you seem to want them too.

This tank has only been functioning since late August man, that is only 3 months, you cannot realistically expect to see miracles happen in that time.

JMHO, and I know what you actually think about my opinion.

[SpokaneReef]

Actually I am getting noticeable growth I just want to get them to grow at the base more then the top.

With the limit of only three lights due to the tank only having three port holes it was recommended to go to a 10K bulb so they encrust better. More light on the base of the corals rather than just the top.

I will run the MH 10K during the day when everyone it out of the house and then run my actinic first thing in the morning and late into the evening when everyone is in the house to look at the tank. So it is still pleasing to the eyes.

Another change we are going to do is removing all the sand from the tank and replace the white crate under the rocks with black, this is not planned for a few months but that is why we want the encrusting to speed up. One of my lfs suggested making these changes and that is why we are even considering it. After all we have quality shops here that know what they are talking about. In some cases it is great to live in spokane where we have experts for our reeftanks.

Thanks for the advise Charlie

[Ninong]

I kind of gather that the HQI is about the same thing as the M80 ballast, why would he have the M80 in parenthesis ????

I think he put the M80 in parentheses to let people know that an HQI ballast is an M80 ballast, as opposed to a standard M58 ballast. The M80 ballast is used with 250w HQI lamps and the M58 ballast is used with 250w probe start lamps. Both are regular magnetic ballasts, as opposed to the electronic ballasts.

[Ninong]

From what I gather from Sanjays site the XM bulb is 95 to 136 after the shield, and depending on the ballast.

That's not what Sanjay said. He said that shielded the 250w XM 10,000K HQI DE lamp is 95 PPFD/7,097 CCT on an Ice Cap electronic ballast and 109 PPFD/7,026 CCT on an M80 ballast. That 136 PPFD number was an unshielded reading. You shouldn't ever run these lamps unshielded.

[Ninong]

Since you already have the M80 ballasts and since they're usually better than electronic ballasts anyway as far as PAR is concerned, let's just take a look at the following numbers using your ballasts.

XM 10,000K = 109 PPFD & 7,026 CCT

AB 10,000K = 104 PPFD & 8,225 CCT

Ushio 10,000K = 84 PPFD & 9,961 CCT

So what does that tell us? It tells us that the XM gets more PAR because it is the LEAST accurate of the three lamps when it comes to matching the advertised 10,000K rating. That's always the case. That's why the 6,500K Iwasaki lamps produce so much more PAR than a decent 10,000K lamp of the same wattage. The higher the Kelvin, the lower the PAR. The lower the Kelvin, the higher the PAR -- all other things being equal.

It seems obvious to me -- based on Sanjay's test results -- that the AB lamp would be a better choice than the XM lamp. It produces almost the same amount of PAR and it has a more pleasing coloration. The Ushio lamp is almost exactly correct as far as correlated color temperature is concerned but the PAR drops to only 80% of the AB or 77% of the XM.

CCT (correlated color temperature) tells you how close the lamp matches a hypothetical black box radiating at a certain Kelvin. In this comparison, only the Ushio lamp comes close to the claimed 10,000K.

Remember that Sanjay doesn't test a whole bunch of lamps and ballasts and individual lamps can vary by 10-20% simply due to manufacturing inconsistencies. If you were to test 10 different lamps of the exact same wattage, etc., from the same manufacturer, they wouldn't all test the same. Anyway that's what Sanjay says.

So, if you want the most PAR regardless of appearance, go with either the XM or the AB. The AB will give you a better coloration -- more white than the XM. If you want the best bluish-white coloration, go with the Ushio but you will lose about 20% in PAR.



P.S. -- Just remember this: Manufacturers make all sorts of claims when it comes to Kelvin ratings. Some of the claims are hilarious! Several years ago, one very well known maker of VHO fluorescent lamps raised their advertised Kelvin ratings much higher than their previous ratings on the same lamps even though they had made absolutely no changes to the lamps. It's all advertising.

[Ninong]

One factor that I forgot to mention is that you should always take into consideration the reputation of the manufacturer. How long have they been in business? Do their products stand the test of time? Do their lamps last as long as claimed or do they suffer from infant mortality, dying during the first three or four months of their lives.

Several years back, a certain brand of 14,000K metal halide lamps were a new fad on all the boards. Everybody raved about them based solely on their appearance. Then we started to see lots of posts from people saying that their brand new 14,000K lamps were failing after only three or four months of service; but they were happy to report that the vendor replaced them with new, crappy 14,000K lamps, no questions asked.

Another point the reefkeepers who switched to those crappy 14,000K lamps overlooked was that those lamps produced less than half the PAR of a decent 10,000K lamp of the same wattage. The only thing they had going for them was their 'pretty blue coloration.'

That particular manufacturer was importing those lamps from China. For whatever reasons, the Chinese have a difficult time with quality control. They have no trouble at all beating everyone else's price but they can't seem to match the quality and reliability of the more expensive lamps produced in Germany by established manufacturers with good reputations for quality and reliability.

[SpokaneReef]

Thanks Ninong

I already purchased the 10K bulbs and the growth is back on track once again. The bleaching is almost completely gone and I have learned a great lesson out of all this.

The is an AB bulb? I went with the XM 10K because of the par and they are on sale for $56.00 each shipped

I also finally got my new reflectors installed too.

The tank is shaping up nicely. Now just sit back and watch the growth....

[Ninong]

The is an AB bulb?

Yes: Aqualine-Buschke 250w 10,000K HQI DE lamp.