MH

[virus530]

Hi All ,

Need some advice.

wanted to get a MH but do not wish to invest in a chiller.

Currently using fan to blow on my 2 by 1.5 by 1.5 tank.

Temp currently at 26.5 to 27.

Was wondering if I place my MH higher from the water surface will it help not to bring the temp of water so high?

From my understanding is that coral can still do well in temp 28.

So I am thinking to get MH but on it for just 4 - 5 hours daily?

Will that works?

Currently using 2 power compact light and 2 flourescence light.

Felt that light not strong enough as the coral not open fully.

Regards

[Tanzy]

Not advisable because your tank is too small. Won't take much to heat to raise the temperature of your tank. All you need is one hot day and everything in your tank will be cooked.

[virus530]

Not even if I just on it for 4 hrs?

Sorry as I know nothing much on MH.

[pospeh]

I run a 250W MH light over my 3x2x2 tank six hours a day. It sits about 18 inches above my tank. I don't use any sort of fans to cool down my tank.

Tempertures range from 28 during the morning to about 31 when the MH lights have been on for 6 hours. I use AC in the room only on hot days. Most of the time, its just open windows.

The only reason I like MH light is the shimmering effect, and not because the light is stronger.

In my tank, the clams do just great, as does all the soft corals. I haven't had success with SPS corals but the LPS corals do open up well.

A 150W unit should be enough for you. With fans, you should be able to bring it down to 29 and below. Just make sure you keep it under 32C or the hard corals will definitely die.

Lots of people in the U.S. keep their tank at a constant 28 and see better growth in the corals.

But your tank is so small, I think it would be a waste economically to use MH on such a small tank. But you can always get a one bulb unit now and then use it later on a bigger tank (up to 3 feet) when you decide to upgrade.

[mv3i]

yah , would stongly advise against MH for 2 ft ..... dun think even the ac fan can cool the water enough during the MH is on .... even if you can .... you need to top up quite a fair bit of water ...

[hotsoup]

U dun have to go to the extreme to own MH for a tank's height that's less than 2 ft. PL light will do the trick

[anakjoh]

My 150W MH is about 10 in above water level. I use a fan and most times temp's at 27C. Early morning, 25-26, max 29C. MH is on 7 hrs. I guess temp is controlled because there's no other light except a 20W actinic. BTW the tank's 2 x 1.5 x 1.5.

I didn't buy MH for marine - it was originally for FW but obviously supersede the requirement.

[virus530]

Hi All,

Thanks for all the feedback.

Does Coral do better with MH compare to FL or PL light?

anakjoh....wat was your temp before you use MH?

For mine...original is 29.5 but after using fan....it manage to go down to 26.5 - 27.

Anyway,anyone can recommend any brand....price.....and possible the LFS to get it.

Appreciate all your help and advice.

Will take everyone advice into consideration before doing anything.

Regards

[Earthborne]

Hi, just one suggestion here.

U may try MH (max of 150W for yr small tank), hang it atleast 18inches from water and place a large glass plane over yr tank ( but don't cover everything , u need gas exchange). Use a fan to cool/blow out the column of warm air trapped between glass plane and MH. In this way, u may lower the water temp w/o suffering a killer evaporation rate.

G'luck

[Morgan]

Hi, just one suggestion here.

U may try MH (max of 150W for yr small tank), hang it atleast 18inches from water and place a large glass plane over yr tank ( but don't cover everything , u need gas exchange). Use a fan to cool/blow out the column of warm air trapped between glass plane and MH. In this way, u may lower the water temp w/o suffering a killer evaporation rate.

G'luck

Hi there

Just to clarify, cooling is done by expediting the evapouration rate using fans so how does the tank water cools down if the evapouration rate is low.

[mv3i]

professor morgan has spoken again

[Tanzy]

The glass cover might cause green house effect and increase the temperature of the tank. The only way to reduce temperature without evaporation is to use heat exchange through conduction (chiller).

[Morgan]

professor morgan has spoken again

Hey since when?

[mv3i]

btw , saw your new tank pics at pbase ... awesome .... btw ... juz a suggestion for the phototaking ... can also get a tripod

[Morgan]

for your compliment.

Do not have a tripod at the moment, should be getting 1 soon.

[virus530]

so will my coral turn out better after using MH compare to FL or Pl?

[Tanzy]

What corals do you keep? Some don't require MH.

Assuming all other factors are met, including temperature, corals will gnerally do better with increased lighting.

[virus530]

currently having some hammer branch...not opening too well.

Octopus coral....not too bad

Cateye....okie but bubbles not well pack.

star polp......not open fully recently due to I just change their position yesterday

sea fan....doing very well

buttons.....never see whole thing open...sometime here open sometime there open....nver open all at the same time.

You a member of www.arofanatics.com?you can view my tank there.

recently my coral just suddenly all not doing well thus really need all the expert help i can to bring my tank back to full of life again.

[Tanzy]

For the corals you keep, they won't need anything more than a 150W MH, in fact they can be kept with FL or PL if enough are used.

Your corals not doing well could be due to many reasons other than light. What's your pH, salinity, calcium, alkalinity, nitrate, phosphate levels?

[ACCK]

hi v530,

tanzys rite.i feel yr corals r not openg not so much due to lack of lite.cos a single actinic alone can make all the cor open.thats my experience.

at 1 point i also faced same prob.i was baffled.then i realised tt i hvnt checkd my salinity 4 a wile,due 2 hydrom broke n not replaced.but once i remedied the salinity,everythgs been fine

till 2day.

hope u can find the cause soon

[dodo]

cos a single actinic alone can make all the cor open.thats my experience.

hmmmm....tat's interesting

learnt something here...though nothing concerning actinic

[mv3i]

maybe a 200W actinic ....

[virus530]

Hi mv3i,

I think you meant 2000K rite?

Anyway,Like to thanks everyone for y7our adice.

I have decided against the MH liao.

I am switching to use 4 PL.

Thus total 144W.

The is will bring to more than 4W per Gal.

Which i think is sufficent for my tank liao.

Thanks again everyone.