View Full Version : Flow Help

06/07/2010, 07:19 PM
In my 29g which is 30" long I need to know what powerheads to put in for best flow, I have two k2's right now but it seems to be not enough.Any ideas, thanks in advance

06/07/2010, 07:31 PM
You could try a K3 or a maxi-jet 900. I was really disappointed with my K2's. My maxi-jet 1200 rated at 295gph is waaaaaay more powerful than my koralia k2 rated at 600+gph.

Don't try a K4, you will blow all the water out of your tank.

06/07/2010, 08:00 PM
Now are you saying the K3 or mj plus my k2's?

06/07/2010, 08:09 PM
I'd start by replacing one of the 2's with a 3.

06/07/2010, 08:11 PM
I'll start by asking which corals you keep or plan to keep.

06/07/2010, 08:47 PM
Sps, Lps, and one clam, I guess mixed reef to be exact

06/07/2010, 09:05 PM
You're over 40 times turnover for flow. This is fine for what you want to keep. Just try arranging them differently. As your sps begin to grow, you may have to add more.

06/07/2010, 09:47 PM
It just seems when looking at my gravel Im not getting alot of movement, and also I am getting cyno on my gravel only, not on rocks

06/08/2010, 10:34 AM
If you just mean the gravel has cyno, that comes from phosphates and silicates. More info is needed about that. Do you have a fuge? How old is the tank? Do you use RO/DI water? Tank parameters????

06/08/2010, 03:44 PM
I certainly wouldn't base an answer entirely on a ratio of tank size to flow. 30" is a fairly long tank, and you're going to need a good amount of flow to keep the water flowing from one end to the other. What you may want to do is add a third Koralia in the center of the tank. The flow is pretty diffuse, plus what's reflected off the front of the tank should give you a pretty good flow pattern. Although cyano is not "caused" by low flow, that can certainly be a contributing factor as it can lead to a build-up of detritus (which it sounds like you're seeing) which decomposes and releases phosphates and nitrates. I've actually never heard of silicates being a fuel for cyanobacteria. Misled may be thinking of diatoms, or perhaps just knows something I don't.

06/08/2010, 06:23 PM
Hey Mike, silicates can start dinos and cyano. It just won't keep it alive for long, you need phosphates and nitrates for that. I just went back and read through his old posts. The tank is only a few months old. OP, this is kinda normal. Do your water changes and keep up maintenance by siphoning out as much cyano as you can. Go Slow. Nothing in this hobby comes fast!!!!

By the way shakman, I didn't have to go back far to see how long your tank was set up so I don't know if you use RO/DI or not. If not, your problems may continue.

06/09/2010, 12:08 PM
Good to know, Misled. I never knew that about cyanobacteria.