UV heat generation?

[Schulks]

I am considering a UV for my new build but I am worried about overheating the tank.


It is a IM Ext 50 gallon with Trigger Triton 20 gallon sump.

Sometimes my house gets close to 78 degrees. I want to run the UV for parasite control.

Would any UV overheat my tank? Would a 40 watt definitely overheat my tank?

 

[The_Paradox]

It’s going to add several degrees. It’s a 40w heater basically. If it’s an issue though even a small 200w chiller could knock several degrees off.

 

[Schulks]

Trying to avoid the cost and space of a chiller. Maybe I'll just stick with a 25 watt and turn it off when it is hot.

 

[Schulks]

I actually already have an 18w pentair. Pentair says it works for up to 60 gallon aquariums. Should I bother picking up a 25w for my 50g aquarium + 20g sump? or would my 18w do a good enough job?

 

[SpyC]

I actually already have an 18w pentair. Pentair says it works for up to 60 gallon aquariums. Should I bother picking up a 25w for my 50g aquarium + 20g sump? or would my 18w do a good enough job?

I run a 25w on my 50 ext. I have never noticed any issues with heat in my system. If anything, it would just keep the heaters off longer. Our place will hit 76-78 in the summer and the most I have witnessed the tank temp go to is 79.5ish. The normal high is 78.5. I ran a small uv on a 75g system with 30g sump years ago and had no issues with the undersized uv. I just ran the water ran slower through it.

 

[Schulks]

I am going to stick with my 18w pentair for the savings. I'll change the bulb early and keep it near the top end of the recommended parasite flow rate.

I keep going back and forth on installing it inline on return or on its own loop first chamber to return chamber.
@SpyC how do you have yours plumbed?

Here's my breakdown of how I see it right now.

On its own loop it would be easier to adjust the flow between bacteria/parasites. But it would look a lot less clean and take up more space in the sump. Should I drill a couple more bulkheads or just float the pipe into/out of the sump? I could also just adjust the return pump to make up for the flow it would steal from the sump chambers. This doesn't seem like it would reprocess anymore water than inline on return.

Inline on the return would look a lot nicer and take up a lot less space but I'll have to adjust a gate valve and remeasure the flow each time. This is the better option if I don't adjust the flow often.

hmm..

 

[strich]

Curious why you're thinking of getting a UV sterilizer?

 

[gbroadbridge]

I am going to stick with my 18w pentair for the savings. I'll change the bulb early and keep it near the top end of the recommended parasite flow rate.

Make sure that you're sizing for the correct flow rate for Marine parasites.

You need an exposure of 280,000 uw/cm2 for Marine Ich, which is much higher than for Freshwater Ich. If you're working off the chart that show's 90,000 uw/cm2 then you're using the wrong table.

I do not believe an 18W will work on your size tank for parasite control.

 

[ca1ore]

As noted earlier, essentially think of the UV as a heater of that wattage. 40w won't make a massive difference on 60-ish gallons, but it will have some effect.

 

[Malcontent]

I wonder how the wattage is split between the bulb and the ballast (which can get pretty hot)...

 

[The_Paradox]

I wonder how the wattage is split between the bulb and the ballast (which can get pretty hot)...

None as far as an 18w bulb. The bulb draws 18w.

 

[SpyC]

I am going to stick with my 18w pentair for the savings. I'll change the bulb early and keep it near the top end of the recommended parasite flow rate.

I keep going back and forth on installing it inline on return or on its own loop first chamber to return chamber.
@SpyC how do you have yours plumbed?

Here's my breakdown of how I see it right now.

On its own loop it would be easier to adjust the flow between bacteria/parasites. But it would look a lot less clean and take up more space in the sump. Should I drill a couple more bulkheads or just float the pipe into/out of the sump? I could also just adjust the return pump to make up for the flow it would steal from the sump chambers. This doesn't seem like it would reprocess anymore water than inline on return.

Inline on the return would look a lot nicer and take up a lot less space but I'll have to adjust a gate valve and remeasure the flow each time. This is the better option if I don't adjust the flow often.

hmm..

I T'ed off the return to it and used a ball valve to control flow through the UV. The UV output went back into the return chamber of the sump.

I am replumbing the UV with a dedicated pump this week. I will have the output going into the skimmer section this time to help stir up detritus that settles. If it doesn't stir it up enough, I will likely change the output to back to the return chamber.

 

[Schulks]

@strich I want the UV to help with parasite control and be able to toggle it to help with algae. Water clarity is a very nice bonus too.

@gbroadbridge I am using pentairs manual. For the 18w at 37-60 GPH exposure would be 180,000 uw/cm2. Are you saying this is outdated information? Was there some recent studies done? Thanks

Pentairs manual lists up to 60 gallons and I'll be just over that. I figured it would at least help. I could change the bulb early and keep flow on the higher end of recommended.

Edit: oh you mean the pentair manual is based on freshwater ich duh.. so I need 280k uw/cm2 exposure?

 

[PM Corals]

It may bring up your tank a degree or 2. We worked on a 200-250g tank near the beach. That went up 2’degrees when am 80w unit was introduced.

 

[Schulks]

@SpyC So you have done it inline style and going back to its own loop. What problems are you having with inline? I think I will plumb it on it's own then as well.

 

[SpyC]

@SpyC So you have done it inline style and going back to its own loop. What problems are you having with inline? I think I will plumb it on it's own then as well.

I have had no functional problems with inline. It would fill with air when the return was shut off for water changes and this was annoying, but not really a problem imo just an annoyance. I had my tank replaced and decided to get a different stand. My hard plumbing didn't work in the new stand and I had to cut it off. Instead of redoing all of it, I decided to remove the uv from the return.

 

[The_Paradox]

@SpyC So you have done it inline style and going back to its own loop. What problems are you having with inline? I think I will plumb it on it's own then as well.

Inline risks overheating unless you gang the power on the return pump and UV. Separate loop is nice because it’s easier to plumb in a chiller when you realize you need one.

 

[Schulks]

Ok back to inline on return then.. lol

Do you guys target the 280,000 uw/cm2 exposure?

 

[strich]

@strich I want the UV to help with parasite control and be able to toggle it to help with algae. Water clarity is a very nice bonus too.

Just in case you aren't aware - it won't just kill parasites, it will kill a lot of beneficial microbes as well. And algae isn't a bad thing by default - it actually helps in a lot of ways so long as it's kept in check.
I would recommend you use it very slowly if you decide to get one, at least to begin with, and watch what happens.

 

[gbroadbridge]

Just in case you aren't aware - it won't just kill parasites, it will kill a lot of beneficial microbes as well. And algae isn't a bad thing by default - it actually helps in a lot of ways so long as it's kept in check.
I would recommend you use it very slowly if you decide to get one, at least to begin with, and watch what happens.

I'm sorry, but this statement is plain wrong.

First, UV does not kill anything, it sterilises the organism so that the organism is incapable of reproducing.

Second, most beneficial bacteria in a tank are on surfaces, there is virtually none in the water column.