Lighting config for a 3.5'X2.5'X21 inch tank

[honkit]

Dear fellow reefers,

I will be placing a 10KK 400W XM bulb and two 15KK 150W XM bulbs supplemented with two T5 actinic bulbs over a 42 inch (length) X 30 inch (depth - front to back) X 21 inch (height) future tank.

Bulbs will be placed 8 inches above the water surface.

Top two-thirds of the tank will be devoted to SPS corals (mainly acros) and a single crocea clam. The bottom one-third will be yumas, floridas and other types of mushies.

Bare bottom.

What would be your recommended photoperiod for these three MH bulbs and actinics?

My thoughts is on 8 hours for the two 150Ws and a 2-3 hour photoperiod for the 400Ws to simulate the noon sun. actinics one hour either side of the 150Ws photoperiod.

[lightningstrike]

IMHO, 400W for a 3.5 footer with a tank height of less than 2 ft is too much.

assuming u r using 2x 39W T5s,

total lights power (peak) rating= 78W + 300W + 400W = 778W

can ur chiller take the load?

ur mushies and maybe some lps might not be able to take the intensity too (depends on ur coral placement).

juz me 2 cents.

[RAV-65]

Agreed, even without the sandbed, the mushies may get burnt! better to use 2x250W maybe 10KK with a 150/250W in the centre with 20KK (better light spread and colour). Plus combination T5s of blue and actinic...

Juz my preference...

[honkit]

Thanks for the feedback, fellow reefers.

The MH bulbs and fittings have already been bought so I can't change those without considerable expense.

The tank has yet to be ordered - I'll raise it to 24 inches then.

Won't be keeping any LPS - just SPS and mushies (yumas, floridas, discos etc).

[honkit]

can ur chiller take the load?

If my current resun 650CL can't cope with the additional heat, I'll retire it as a back-up chiller and get a custom made 1/2 hp to do the job from an air-con man who's experienced in making chillers with air-con compressors.

[madmac]

Dear fellow reefers,

I will be placing a 10KK 400W XM bulb and two 15KK 150W XM bulbs supplemented with two T5 actinic bulbs over a 42 inch (length) X 30 inch (depth - front to back) X 21 inch (height) future tank.

Bulbs will be placed 8 inches above the water surface.

Top two-thirds of the tank will be devoted to SPS corals (mainly acros) and a single crocea clam. The bottom one-third will be yumas, floridas and other types of mushies.

Bare bottom.

What would be your recommended photoperiod for these three MH bulbs and actinics?

My thoughts is on 8 hours for the two 150Ws and a 2-3 hour photoperiod for the 400Ws to simulate the noon sun. actinics one hour either side of the 150Ws photoperiod.

Very interesting. The 400W, 2-3 hrs may just work well... I don't think it'll burn, if you keep it short. Its the 2*150W that, IMHO, is a tad too little(for 8" away from the water level)... for 21 to 24 ht tank... you won't get the spread. (I used to have 2*150 for an 18" ht tank, water ht is only about 15", and the lights were 4 inches away from the top water, it was quite challenging). I guess if you can still extend the 150s to 10 hrs / or lower the ht to abt 4 to 5" and see from there.

[honkit]

Very interesting. The 400W, 2-3 hrs may just work well... I don't think it'll burn, if you keep it short. Its the 2*150W that, IMHO, is a tad too little(for 8" away from the water level)... for 21 to 24 ht tank... you won't get the spread. (I used to have 2*150 for an 18" ht tank, water ht is only about 15", and the lights were 4 inches away from the top water, it was quite challenging). I guess if you can still extend the 150s to 10 hrs / or lower the ht to abt 4 to 5" and see from there.

Good idea - I will place the 150Ws at 4 inches above the water surface for a better spread. Will place some wooden beams in the hood to accomodate this change.

[lightningstrike]

Good idea - I will place the 150Ws at 4 inches above the water surface for a better spread. Will place some wooden beams in the hood to accomodate this change.

From my limited experience,

dun think a 1/2 hp chiller can deal with the high temp (total contributions from ur lights) when ur 400W MH is switched on, even if it is 4 only 3hrs.

btw, further away ur lights r from the water surface, the better the spread, but u'll lose intensity and vice versa.

[honkit]

From my limited experience,

dun think a 1/2 hp chiller can deal with the high temp (total contributions from ur lights) when ur 400W MH is switched on, even if it is 4 only 3hrs.

btw, further away ur lights r from the water surface, the better the spread, but u'll lose intensity and vice versa.

Will increase it to one hp then.

Wrong use of words - it should read intensity, not spread.

[lightningstrike]

in case u r after an artica or daeil chiller, u can size ur chiller here.

[daimy068]

Good idea - I will place the 150Ws at 4 inches above the water surface for a better spread. Will place some wooden beams in the hood to accomodate this change.

Hi honkit,

Good idea playing around with the mounting height of the MH. Maybe one concern you'd have would be the possibility of water splashing or salt spray onto the MH. Are you using exposed MH or MH fixture?

As for heat generated and chiller size, I think the jbj/arctica chiller sizing calculator will be helpful.

All the best!

[honkit]

in case u r after an artica or daeil chiller, u can size ur chiller here.

Thanks. I won't be using a commercially sold chiller, will use a custom-made chiller with an air-con compressor sitting outside the house like a split air-con unit. The compressor will be a 1.5 hp unit.

One of my reefing friends have this unit done up for his 210 gallon tank and it's worked very well for him.

[honkit]

Hi honkit,

Good idea playing around with the mounting height of the MH. Maybe one concern you'd have would be the possibility of water splashing or salt spray onto the MH. Are you using exposed MH or MH fixture?

As for heat generated and chiller size, I think the jbj/arctica chiller sizing calculator will be helpful.

All the best!

All MH bulb are encased in casings so no worries about splashes.

[RAV-65]

All MH bulb are encased in casings so no worries about splashes.

Dun agree, if there is not glass ( besides the bulb's own protective glass ) to protect the bulb from splashes, the bulb can burst when in contact with water due to the bulb's intense temperature when it's turned on...

[honkit]

Dun agree, if there is not glass ( besides the bulb's own protective glass ) to protect the bulb from splashes, the bulb can burst when in contact with water due to the bulb's intense temperature when it's turned on...

The bulb casing comes with a GLASS cover to protect the bulb from splashes.

[lightningstrike]

Thanks. I won't be using a commercially sold chiller, will use a custom-made chiller with an air-con compressor sitting outside the house like a split air-con unit. The compressor will be a 1.5 hp unit.

One of my reefing friends have this unit done up for his 210 gallon tank and it's worked very well for him.

an artica commercial unit is little diff from the split air-con unit design u hv juz mentioned. juz take note to size the condenser, condenser fan, heat exchanger, etc accordingly. hv fun wif ur incoming new chiller.

[daimy068]

The bulb casing comes with a GLASS cover to protect the bulb from splashes.

Hi Honkit,

Think that might be what RAV-65 is saying. Even the UV glass cover on the fixture might crack (hopefully not shatter) due to its intense heat upon contact with water that's about 25-27 deg if the MH is placed too near the water. Think 6" above the water might be safer.

Just thinking about preventing sh*t from happening.

[honkit]

Hi Honkit,

Think that might be what RAV-65 is saying. Even the UV glass cover on the fixture might crack (hopefully not shatter) due to its intense heat upon contact with water that's about 25-27 deg if the MH is placed too near the water. Think 6" above the water might be safer.

Just thinking about preventing sh*t from happening.

Point noted. Will place accordingly.

[honkit]

an artica commercial unit is little diff from the split air-con unit design u hv juz mentioned. juz take note to size the condenser, condenser fan, heat exchanger, etc accordingly. hv fun wif ur incoming new chiller.

Have spoken with the reefer on this - he's got everything spec out for me.

Like you said, will be fun.