New here, flow rate questions.

[Gplus]

Hello all,

I am new here at Reef Central. I was recently bit by the SW bug so I've been giving the subject all the attention my freshwater planted tank allows over the past 2 months. I feel that I have the basics figured out. I'd like to give you all an outline of my tank thus far then ask a question I can't figure out on my own...

The tank, an Aqueon 15g tall/column, 7 weeks old. For equipment I'm running a AquaC remora S skimmer and two hydor koralia nano 240 power heads. Lighting is a retrofit RapidLED fixture (3 neutral white, 4 royal blue , 2 420mn violet) ..The tank was started with live sand and 15+/- LBS of uncured live rock..I introduced a CUC two weeks ago ( a few hermits, few nerites and one turbo snail. I let it run its course while sucking out die off and doing water changes. . A Solid cycle took place. Just today I added an ocellaris clown pair
Ammonia 0 (over 3 weeks)
Nitrite 0 (over 3 weeks)
Nitrate around 5mg/L

Sorry for the long list of information. From what I've noticed most members ask for a basic description of the OP's tank.

My question... My two clownfish seem to be swimming around quite a lot even once the lights turned off. I'm trying to decide if two koralia nano 240's and a Remora S (run by a maxi1200) is to much flow. I have both power heads mounted on the back of the tank.. One on the bottom left and one on the upper right. Total flow is about 770gph. I feel its a lot for a 15g tank. For tonight I unplugged one of the koralias. I'm looking for recommendations pertaining to how much flow is enough/to much or best placement of the my current equipment.
Thanks a lot!

 

[dustinkimpel]

If this is a 15 gallon tank you definitely only need 1 powerhead going. It's not so much the flow rate as the fact that everywhere in your tank is under direct powerhead blast, which nothing wants. You want your powerhead to be moving water without it blasting to much of your tank.

 

[Dkuhlmann]

I think you're ok having the two powerheads but try this. Mount them on the sides of the tank with them aimed at each other, this will create an erratic flow that most corals like. It will also make it easier for your clowns to find their sleeping place. I don't think you have too much flow unless you plan on doing LPS corals. Every tank is different in how much flow is needed due to how your rocks are placed they have a lot to do with changing how the water moves by blocking or allowing flow around your tank. You ultimately want the water to circulate everywhere that it possibly can and help keep detritus from collecting in one spot and going through the filter system. If it does collect in one place no problem you can vacuum it up when you do your water changes.

Welcome to Reef Central!

 

[Gplus]

Thanks for the quick replies and warm welcome! I will try aiming the powerheads at each other and see what difference that makes! I originally put one at the top and one at the bottom because I was was worried about flow at the bottom ( the tank is 24in tall). If that is still too much maybe I'll switch to one powerhead or, get rid of both and buy a wavemaker!