Acrylic vs. Glass

[robertfah]

I've got about a 30g sump made from acrylic for my 90g tank. I used to have a 55g glass sump for my 155g tank prior to this. I had no issues with my water temps rising during the day. But just yesterday I had a temp spike up to 90 degrees in my tank and I can't figure out why. Would the acrylic tank be more suseptable (sp way off...lol) to holding heat vs a glass tank? I can't figure this one out, but in the meantime, I've put a fan on the sump and it dropped it down to 80 but I also lowered the AC in the house. Here in FL, it's been 95+ for the past 2 months, not to mention the heat index getting over 100....but my house AC is set to never get over 84.....I would think that would be enough to keep the tank neutral at 80-81 degrees.

Any ideas?

 

[mrg02d]

Acrylic does insulate better, but not enough to cause a huge spike in temperature.I have a 20g acrylic tank and I live in florida too and am dealing with the heat as well. You need to run the AC more. I know it costs more, but its the best way to keep that tank cool. I keep my place at 76-77F and my tanks never go over 79F. Going to 90F suggests your heater may be failing, unless your house got up to 90F. Just one more month of the heat and we are in the clear!

Matt

 

[Deep Seven]

Acrylic has a thermal conductivity rating of 0.2
Glass has a thermal conductivity rating of 0.96

Thermal conductivity is a measure of how fast heat (or cold) is transfered through a material. The lower the number, the better "insulator" it is. Acrylic will prevent the transfer of heat 5 times better then glass. Although, if the surrounding air is hotter then the tank water, the acrylic should help keep it cooler.

Cold water tanks use acrylic usually to save on the cooling costs.

 

[robertfah]

Acrylic does insulate better, but not enough to cause a huge spike in temperature.I have a 20g acrylic tank and I live in florida too and am dealing with the heat as well. You need to run the AC more. I know it costs more, but its the best way to keep that tank cool. I keep my place at 76-77F and my tanks never go over 79F. Going to 90F suggests your heater may be failing, unless your house got up to 90F. Just one more month of the heat and we are in the clear!

Matt

Yeah, we dropped the AC down to 76 during the day and 74 at night (we've always kept it at 74 at night though) so we'll see if it helps. I just bought a little fan and it seems to be helping with the temp a little. I am also wondering if it's worth it to make a cover for the part of the sump that is open, to try to keep the moisture and what not inside...???

I also unplugged my heater right away, even though it was set to 77, it could have crapped out and caused the spike in temp. Don't know for sure but I'll prob. test it out again in a couple of months when the "cooler" weather arrives and the tank may need a heater.

Acrylic has a thermal conductivity rating of 0.2
Glass has a thermal conductivity rating of 0.96

Thermal conductivity is a measure of how fast heat (or cold) is transfered through a material. The lower the number, the better "insulator" it is. Acrylic will prevent the transfer of heat 5 times better then glass. Although, if the surrounding air is hotter then the tank water, the acrylic should help keep it cooler.

Cold water tanks use acrylic usually to save on the cooling costs.

WOW....great information there.....thanks a bunch.

 

[Deep Seven]

I am also wondering if it's worth it to make a cover for the part of the sump that is open, to try to keep the moisture and what not inside...???

Only do this if you're worried about water loss or you start using the heater. Evaporation = heat loss. If you add a small fan blowing at the open part of your sump it will add to the cooling, but also increase evaporation.

 

[robertfah]

Only do this if you're worried about water loss or you start using the heater. Evaporation = heat loss. If you add a small fan blowing at the open part of your sump it will add to the cooling, but also increase evaporation.

Intersting dilemia huh? LOL.....I think I'll play it by ear but my original thoughts were to find a larger sump that I could house 1 or two more pumps in (for various reactors or uv sterilizer, etc.) because this sump, while desinged nicely, is setup rather poor; I cannot get at the bio balls to remove them and put live rock in it's place. It seems they put them in and built the walls around it, essentially sealing them in there.

I'm sure I can find a 40-55g tank on craigslist for close to nothing and design another one as I did before.....we'll see though.

For now, I'll stick with the open sump and the small fan that's blowing on it. If evaporation gets to be too much, then I'll try a lid, although I have a hose and the top of the skimmer sticking out so I'll have to get creative with the lid.