Cooling down my tank


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I have a 90g setup I'm having temperature problems with

Currently I have four t5 bulbs And a Rio 2100+ Submerged in my sump there's 4 t5sonn the sump also and I'm adding another 4 bulb t5 to the tank. I also run a fluval 405. Currently I have no fans on the tank.

My tank runs at about 81 or 82°F in I needed at 77 I need to lower the temperature a few degrees and it will get hotter the summer so I'm concerned. I'm trying not to buy a chiller so I want to use fans.

I have a 9" canopy I currently don't use.

I want to use the canopy and I'm thinking if I put some fans on it it may help with my heating issues. I want to put 5 fans on 3 in the front blowing in across the water and two on the sides blowing out.

Ill also add a fan or two on my sump hopefully it will help.

Should I use the canopy or not and where and how should I add fans.
Most people just use the little desk fans you can get at Walmart or somewhere similar. I'd start off with one, though. Be prepared to top off a lot more.

For the record, 82 is what I run my tank at. There's no issue with that temperature.
I run my 37 gallon (12" x 30" surface area) at 78.4 degrees. I have 2 computer fans 2 inches off the water pointed straight down. Its been working for me but I dont think ive had the room hotter than 84 degrees. My ato reservoir has run dry twice so you definitely will have at least twice the evaporation as before depending on conditions.
@ErinCahir: I will have to pick up some desk fans although I don't go to Walmart around these parts lol. It's a seahorse tank so they like it a little cooler around 77 or 79

@captain Ron. I have two computer fans with a power adapter how did u mount them?
I keep my tank around 79°. I live in the desert so this summer will be the real test. Light wise i run 3x 80w T5HO and 3x LED flood in DT and Ebay LED panel for fuge. Heater is on a timer to counter act the heat from the T5s. For cooling i have a 6" desk fan in the hood in a back corner angled towards the front of the hood on the same timer as the T5s. Also have another fan in the sump but haven't been using it (yet). Temps go from a peak of 79°to a low of ~77°at night. The few fish i have in the tank don't seem to mind the swing in temp. IMO, i think it mimics nature pretty well since the ocean naturally cools a few degrees at night. We'll see how corals like it when i start adding them this week...
It's probably normally 85° around here. But it can definitely get higher up to 100° and humidity is really high too so I'm hoping evaporative cooling method will work if not I'll have to put in a chiller or run my ac 24/7 which is pricey! I'm gone for 10 hours every day so I want to be able to keep everything at temp
So I added two fans just now. Ill monitor the temp and see how it goes. Pictures:

I think you'd have better luck with having them blow across the tank (maybe next to each other or opposite sides). They way they are positioned now they're going to get a TON of salt buildup.
They would be harder to mount that way. I'll see how this goes and adjust if necessary. I just put them on the easiest way possible.
So it's been a while and the temp has dropped 3 degrees! My experiment went well so now I just have to figure out how to mount them with my 8 t5 bulbs
So I added two fans just now. Ill monitor the temp and see how it goes.

I'm flattered, you took me literally! :-)

I have a plastic mesh screen I built (google for the BRS videos if you are interested), so since I was lazy I just have the fans laying on the screen. I have them connected to a power adaptor for a harddrive usb kit and I have the adaptor plugged in to my Apex Jr. Which I have programmed to turn on if the temperature starts to rise. I have had this setup for a few weeks now and I have zero salt buildup on the fans. I think what will determine salt buildup is if you have teeny tiny bubbles bursting on the surface which would give a fan salt spray and when that evaporates you are left with the salt. To visualize pour yourself a Sprite and look very closely at the surface and if the Sprite isnt flat you will see what I mean. Originally I had bubbles from my skimmer and the salt was everywhere!

-Capt. Ron
I use an eggcrate that is cut to fit across the tank and put the fans on top of them. I use a ziplock bag and stuff all the wiring in it because you will get major salt creep.
2 fans won't cut it based on the temps you're telling me. You need to get a steady flow going across the tank to 1) cool via evaporation 2) move the air along so you don't have this mini-greenhouse effect from the lamps.

You will likely need an ATO system from the evap once it gets going because the evap loss will be major.
Seahorses need to be kept closer to 70 degF, otherwise you are going to eventually have serious issue with bacterial infections.

Also, seahorses do not do well with a lot of light, 8 t5 bulbs is not going to make them happy. I would reduce the amount of light over tank and make sure they have some safe shaded areas for them to hide.
Ocean rider says to keep my seahorses at 75-78. I will have lots of shade for them with corals and plants. The tank is not done and I currently have 4 bulbs on it. If I need less light I can use less thank you for your help
Update: one of the fans did rust out. I heard a POP! And it blew out.

I changed the fans so they're on an angle. I just held them at an angel and drilled in some screws! I also bought a fan from Meijer and mounted it to the wall it keeps my lights super cool and even gets to the water.






When it gets really hot I point the fan under the stand also.
Finally, I run my sump lights opposite of my tank lights now. I have a 24" 4 bulb T5 on my refugium which get pretty hot under there. I'm changing the sump out to a 50g soon.
Yes but you want to put saltwater in bottles and freeze them then throw them in. If you use straight ro/di water if it leaks it will lower your salinity. Plus salt water will get a little colder!