Heater effectiveness..

[Valentini89]

How effective are 2 smaller heaters placed in a sump vs one large? I can't find a decent heater that will fit in my sump. I only have 13" in the widest area.

[Anemone]

I like two smaller heaters better. If one fails (and they generally fail in the "on" position), you still have the second one and some time to notice the problem.

Kevin

[Tripod1404]

Originally Posted by Anemone

I like two smaller heaters better. If one fails (and they generally fail in the "on" position), you still have the second one and some time to notice the problem.

Kevin

My stand is the opposite. Two heaters mean, two times the chance you will have a heater failure. Since one heater on its own cannot compensate for the second heater, you are essentially still dependent on one heater and have two times the risk of a heater failure.

If one fails on the "off positions", the other one would not be able to keep up the temperature. So the tank will still cool down.

If one fails on on position, it might take days before you realize it. As a single heater would not be able to heat the tank on its own, the tank will cool down slowly until the second heater kicks in and heats it up. All this time one heater will be constantly on. Since everything looks normal, it might take days before you can realize it is "constantly on". A heater that is constantly on is dangerous. Best case it will broke down on stop working, worst case it will explode.

IMO a single heater on a temperature controller is much safer. If it gets stuck on "on position" controller will still turn it off. If it gets stuck on "off position", the controller will inform you (depending on the brand of the controller, this can be emails, chimes or a light)

[Gorgok]

I like two heaters at about 75% tank rating or so. So a single failure off will take a while to drop down, giving me time to fix it even if i cant get a new one right away. A single on failure will only really be noticeable in the temp graph of the tank, with a much more gradual down swing and longer off cycle, but without that sort of info it would be hard to spot. Still better than cooking the tank.

My heaters are on a controller, with their own temps set higher than the control will stop at. If control fails (like some dummy forgets to put the probe back in the water...) then they will still stop heating on their own a degree or so above what i actually want, but nothing too bad.


Size wise in general, two 100w heaters is a 200w heater. They will both heat the tank the same amount and use the same power. A watt is a watt.

[mcgyvr]

Using 2 heaters if you can't fit one is totally fine and just as effective..

[tthouston]

I have been reading somewhere the tank crash because the heater failed it keeps ON and up to 95 degrees, so with my opinion the heater should connect to Apex so the power will shut down if the temperature reach to the highest point.
IMO, I like the heavy duty 300W heater than small one and I will add one more on winter. Both are controlled by Apex.

[hkgar]

Originally Posted by Tripod1404

My stand is the opposite. Two heaters mean, two times the chance you will have a heater failure. Since one heater on its own cannot compensate for the second heater, you are essentially still dependent on one heater and have two times the risk of a heater failure.

If one fails on the "off positions", the other one would not be able to keep up the temperature. So the tank will still cool down.

If one fails on on position, it might take days before you realize it. As a single heater would not be able to heat the tank on its own, the tank will cool down slowly until the second heater kicks in and heats it up. All this time one heater will be constantly on. Since everything looks normal, it might take days before you can realize it is "constantly on". A heater that is constantly on is dangerous. Best case it will broke down on stop working, worst case it will explode.

IMO a single heater on a temperature controller is much safer. If it gets stuck on "on position" controller will still turn it off. If it gets stuck on "off position", the controller will inform you (depending on the brand of the controller, this can be emails, chimes or a light)

If it takes a 100 W heater, why not use 2 100 W heaters. Heating time should be got in half and no additional cost and you then have redundancy.

[Tripod1404]

Originally Posted by hkgar

If it takes a 100 W heater, why not use 2 100 W heaters. Heating time should be got in half and no additional cost and you then have redundancy.

But OPs question is about using two 50W heaters rather than one 100W.

[mcgyvr]

Originally Posted by hkgar

If it takes a 100 W heater, why not use 2 100 W heaters. Heating time should be got in half and no additional cost and you then have redundancy.

If both heaters fail on you can cook the tank..
If it only takes a single heater then its entirely possible that said single heater can only heat the tank up to 85 deg F max.. Having twice the heating power may cause the tank to reach 95 degF should both fail on..

Just stating a reason for not wanting too much heating power...

[hkgar]

I use an Apex controller, so it would require a double failure. If the heater fails on the controller would also have to fail on. But anything can happen. Heck Virginia lost and so did MSU.

[Tripod1404]

Originally Posted by hkgar

I use an Apex controller, so it would require a double failure. If the heater fails on the controller would also have to fail on. But anything can happen. Heck Virginia lost and so did MSU.

Lol I am very scared of heaters since one guys sump was blown by a heater that failed and exploded.

[ryeguyy84]

I had a single heater that failed in the off position. With the Apex they could fail in the on position all they want, it's the off I'm afraid of. Even though it was controlled by my Apex it still took me a while to notice because it happened at night. I woke up to tons of texts warning me but I still had a tank at 65 degrees. Would have like a secondary to keep things going.

Now I run 2 and it helps me sleep at night.

I also programmed a virtual outlet so if the heaters on for an abnormal amount of time it sounds the alarm

Sent from my SM-G950U using Tapatalk

[pisanoal]

Originally Posted by ryeguyy84

I had a single heater that failed in the off position. With the Apex they could fail in the on position all they want, it's the off I'm afraid of. Even though it was controlled by my Apex it still took me a while to notice because it happened at night. I woke up to tons of texts warning me but I still had a tank at 65 degrees. Would have like a secondary to keep things going.

Now I run 2 and it helps me sleep at night.

I also programmed a virtual outlet so if the heaters on for an abnormal amount of time it sounds the alarm

Sent from my SM-G950U using Tapatalk

I agree here. I run 2 titanium heaters with their own thermostat on a reef angel . One is set as a backup and comes on at lower temp then the primary is set to if the heating element should go bad. If the relay happens to stick on, well the heaters thermostat will catch it. The likelihood if both faiming simultaneously is small enough for me to feel comfortable.
I've gone through probably 15 heaters trying to find good ones for quarantine. Ive only had 1 or 2 that stuck on. The rest didn't come on when they were supposed to or just didn't get hot.

Back to OP, I dont see an issue with it. Just go with quality heaters. Titanium would be my recomendation so you dont have the cracking/exploding concerns doubled.

Sent from my VS988 using Tapatalk

[Kevin Guthrie]

A watt is a watt, whether it comes from one heater, more than one, or a submersible pump it will heat the water just the same.

IMO you are better off with multiple smaller heaters, both in terms of eveness when they are OK, and in terms of the risk of boiling your tank, which happened to me in my pre-salt days. Say you have 3 heaters and one fails to come on, the temp in the tank won't get too low because the others are functioning OK and can make up for it. But too hot is worse than too cold, and one massive heater on 24 hours can sure raise the temp a lot farther than one small one.

[Valentini89]

Thanks for the advice everyone!!