Flow Help - 30g - 24"x20"x16"

[blakki73]

Hello everyone,

My first reef tank has been set up for a bit over two months now, and it's doing great, I already see significant coralline growth, having started from dead mined rocks.

That said, I have noticed a problem, I have two Jebao ELW-20M (3000-10000 l/h, 790-2641 gph), since the price difference with the smaller models was negligible, but now I think they are just too big. I preferred going bigger also in case I decide to upgrade my tank one day.

They are both set at 30% (3000l/h, 790g/h), linear flow, with one running at all times, and the other turning on for 5 minutes on the hour. They are positioned at the back of the tank, towards the top, against each other.

The reason why I think they are too much, is that the branching hammer I purchased 1 month ago is not extending as it was in the shop, although it is showing some growth even, having formed a new head.

Parameters are all in the norm:


Kh 8-9
Ca 430-450
MG 1400-1450
Nitrates 2.5-5
Po4 0-0.05

Lights are NooPsyche III, 60% Blues, 40% Violet, 30% Red and green, 15% whites, running 8 hours with ramp up and down.

My question is, should I just get smaller wave makers instead, or should I find a way to do with what I have? Another annoying detail is that I can't use the random feature, because you can't set an upper limit for that.


Thank you!

 

[Jekyl]

Couple things. With a 2 month old tank you're probably not seeing coraline and the retraction could be due to the tank age.

Usually coraline starts showing up after the ugly phase. Which could be any time from months 4 or 5 and can last up to the year mark.

To get a better idea and better advice, include a short video of your coral with issues using white lighting.

LPS can be difficult in new tanks, best to get all the info possible.

 

[blakki73]

Thank you very much for your response, here's a video:


Admittedly it is a bit better, even though I still think it used to be fuller in the shop, since yesterday I relocated the wave makers to the sides, instead of being on opposite sides on the back wall.

At the end I also show the coralline growth, with the lights on 100%.

I am still debating whether or not I should buy smaller wave makers, so they could be on at the same time.

 

[Mr. Mojo Rising]

In my opinion its not too much flow, it looks good, except for the torches in front which are obviously leaning over to one side, they need more random flow rather than one way linear flow. Personally I like more flow in my tanks. More flow will also help with the algae issue coming up.

That is not coraline, looks like diatoms to me and the beginning of green algae, very normal in a 2 month old tank.

 

[blakki73]

Oh I didn't know there was bright pink diatoms, good to know.

I went already through the brown diatom phase, lasted 2 weeks approximately, then gha and that fluorescent green film started approximately 2 weeks ago, together with that purple stuff all over the tank and some on the power heads.

The point is that only one pump can run constantly at this point, if both run it becomes way too much I think, and stuff starts retracting.

Torches are not in their final position tho, I'd like to get them on top of the right side rock, just waiting on the frag rack to get here so I can start acclimating to higher light progressively.

 

[Jekyl]

I don't see WaveMaker position in the tank. However one on each side, 1/3 of the way down, pointed towards each other and slightly upward is a good place to start. You want them creating surface agitation. This will also help you from "too much".

 

[blakki73]

Thank you for the response, I'll experiment some more tomorrow, hopefully I can figure something out.

Is there any way to mechanically reduce the flow coming out of a wave maker? I was thinking about rubber banding a coarse sponge in front of it, would that do anything?

 

[Jekyl]

Thank you for the response, I'll experiment some more tomorrow, hopefully I can figure something out.

Is there any way to mechanically reduce the flow coming out of a wave maker? I was thinking about rubber banding a coarse sponge in front of it, would that do anything?

Aim upwards more. Surface agitation is a good thing and will reduce the direct flow even more.

 

[blakki73]

This is what I managed:


Honestly I feel like the hammers just don't like it.

I'll give it a few hours like this, maybe it just needs to get used to it.

 

[I never finish anythi]

Try one pump on a pulsing mode and the other on a random setting .

 

[blakki73]

Random mode on Jebao will not allow you to set an upper limit, which means one pump would go up to 10000 l/h.

When I activate that, all the corals will close within 5 minutes.

Currently they are master/slave, set at 30% (the minimum) sine wave.

 

[blakki73]

After a day, hammer is looking like this, I'm starting to just think I need smaller pumps.

Does anybody know if using sponge in front of the pumps would do anything to reduce their output?

 

[dansyr]

I don't think that's too much flow overall, just positioning is going to be the pain. Maybe try them not symmetric, if that makes sense? like one going up + towards back wall, other how it is? or other going down + facing the other powerhead, to keep from the 'fountain' effect.

Looks like right now the issue is water going up + washing down the front wall if I'm envisioning flow right. Could also move the corals back a bit closer to the central rock, the flat surface of glass makes it really hard to get non-laminar flow

 

[blakki73]

I will experiment some more in the next days, flow is the main think I have to perfect now, I really appreciate all your help.

I'll report back if I manage to improve it

 

[Jekyl]

I will experiment some more in the next days, flow is the main think I have to perfect now, I really appreciate all your help.

I'll report back if I manage to improve it

Could use a mesh bag over top. Have to clean it regularly though.

 

[blakki73]

I think I've got it, this is with both pumps running 30%, master/slave, classic wave 60% frequency.


It looks like the euphyllia are moving gently and randomly.

Thank you all for the precious info and advice!