Messed up my Flow

[EricR]

I inadvertently messed up the flow in my 40 gallon breeder when I switched from 2 smaller HOB power filters on the left and right (back) to one larger HOB on the left only. (No room for sump so HOB filtration only, single Nero 5, 2x AI Prime 16 HD LEDs)

4 different kinds of zoas that had been doing fine have now been closed for a couple of weeks, starting shortly after the HOB configuration change. (All zoas added 1/2022-5/2022)

Couple of ricordea Florida getting blasted and started to wander off the rocks. (Ricordea added 7/2022)
*Visible divot/trench in the sand across (up current) from them started forming due to the flow change.


Here’s a picture showing old/new HOB locations and Nero 5 powerhead that had been in this same location with same schedule/settings for more than a year,,, also no changes to lighting schedule:

My theory is that removing the HOB that was above the zoas caused a massive decrease in flow/turbulence there. (Also the new, stronger HOB on the other side caused current increase forward and into the path of the Nero powerhead which pushed stronger flow across the path of the ricordea)

***Moved my Nero to the right side of the tank (still upper front/middle) and I think that mostly fixed flow to the ricordea but not confident about the zoas.

At this point, I’m just kind of randomly moving my Nero to different locations and trying to judge flow over the zoas with dental floss tied to a straw but not really sure what I’m looking for (since I never had an issue before so never paid that much attention).
*not having luck getting a lot of flow over the zoas so far, but there is VERY LOW flow there,,, not stagnate.

Considering buying a Nero 3 to put across from the Nero 5, or maybe on the back.
*or maybe a super cheap, tiny powerhead I can experiment with.
Afraid to remove the 3d-printed anemone guard from my Nero 5 (been on there since day 1) due to reading horror stories and my urchin/starfish/shrimp climb all over it. (Might buck up and just try it though)
*maybe put one of the rocks with zoas down on the sand in the flow near the ricordea for a few days just to see if any open?


Sorry for the long post but any suggestions?
Any tips on how long zoas can stay closed trying to adapt to changes before they die out?

 

[Saltyreef]

Did you switch from a different brand too?

The seachem tidal you have on there now pulls from the bottom tube as well as the surface. If i recall, you can close the intake to be 100% surface skimming only. Have you messed around with that?

In general the flow from 2 hob filters would break a cross flow from your nero better than 1 regardless of size as ive experienced with using multiple hobs.

I would move the corals around to be best suited for the flow vs repositioning your pump as you want the pump in the perfect spot to not create any dead areas and be able to blow settled detritus out with ease.

 

[EricR]

Did you switch from a different brand too?

The seachem tidal you have on there now pulls from the bottom tube as well as the surface. If i recall, you can close the intake to be 100% surface skimming only. Have you messed around with that?

In general the flow from 2 hob filters would break a cross flow from your nero better than 1 regardless of size as ive experienced with using multiple hobs.

I would move the corals around to be best suited for the flow vs repositioning your pump as you want the pump in the perfect spot to not create any dead areas and be able to blow settled detritus out with ease.

Yes switched brand but my biggest issue (I think) is like you said, 2 HOBs breaking across were better (especially since now I'm completely missing the crossflow directly over the zoas).

New HOB:
Seachem Tidal 110 turned down quite a bit -- did that day 1 since full flow was more than I wanted.
*haven't played with the surface vs tube intake balance much so that's a good idea

Old HOBs:
Marineland Penguin 100 (100 GPH) on left
Top Fin PF40 (200 GPH) on right over the zoas

I don't want to completely redo my aquascape but I could temporarily move one of the rocks (with zoas) just to see if it helps those and go from there.



Here’s a picture of how bad the zoas are looking after about 2.5 weeks of being closed up:

 

[Tlledsmar]

Just a thought... could the new HOB be filtering much more out and the zoas now starving?

 

[Saltyreef]

Just a thought... could the new HOB be filtering much more out and the zoas now starving?

Worth a look.

These tidal filters are extremely effecient the 110 could be overkill for the tank if running certain medias or polishing the water too much.

 

[Tlledsmar]

Worth a look.

These tidal filters are extremely effecient the 110 could be overkill for the tank if running certain medias or polishing the water too much.

I know I killed all my zoas during a move when I transfered everything into a new tank that was too "clean" (even though I used old LR) there just wasn't nutrients enough and I didn't get my coral foods fed in soon enough (really complicated drawn out move) basically they starved off within a couple weeks is all I can figure

 

[EricR]

Just a thought... could the new HOB be filtering much more out and the zoas now starving?

Good thought but I think I'm OK there.

Original post was already long so avoided posting parameters but here's more detailed info on that note:

SG = 1.026 (Tropic Marin always pretty close to 1.0260 within a few .0001)
Temperature = 77 d F (InkBird set 77.0-77.5)
NO3 = 9.1 ppm (Hanna HR)
PO4 = 0.08 ppm (Hanna ULR)
Alk = 7.7 dKH (Hanna and Salifert actually match surprisingly)
Ca = 440 ppm (Salifert)
Mg = 1350 ppm (Salifert)
pH — never really check but pulled out old Red Sea and showed 8.2 but reference chart steps are just 8.0, 8.2, 8.4


I don’t dose alk/Ca as my few soft corals don’t seem to consume much if any between water changes.
*I do dose Trisodium Phosphate daily and have caused some swings but mostly maintaining 0.06-0.10 ppm

 

[Saltyreef]

Good thought but I think I'm OK there.

Original post was already long so avoided posting parameters but here's more detailed info on that note:

SG = 1.026 (Tropic Marin always pretty close to 1.0260 within a few .0001)
Temperature = 77 d F (InkBird set 77.0-77.5)
NO3 = 9.1 ppm (Hanna HR)
PO4 = 0.08 ppm (Hanna ULR)
Alk = 7.7 dKH (Hanna and Salifert actually match surprisingly)
Ca = 440 ppm (Salifert)
Mg = 1350 ppm (Salifert)
pH — never really check but pulled out old Red Sea and showed 8.2 but reference chart steps are just 8.0, 8.2, 8.4


I don’t dose alk/Ca as my few soft corals don’t seem to consume much if any between water changes.
*I do dose Trisodium Phosphate daily and have caused some swings but mostly maintaining 0.06-0.10 ppm

It could be the zoas are just temporarily getting used to the cleaner water. It may not directly relate to nitrate and phosphate levels over an extended period.
Lighting and PUR has a lot to do with the turbidity of the water and this could be affecting them too.
My zoas have looked like this for weeks on end before and opened just fine after fwiw.
I wouldnt be too worried but keep persistance afoot.

 

[Tlledsmar]

Good thought but I think I'm OK there.

Original post was already long so avoided posting parameters but here's more detailed info on that note:

SG = 1.026 (Tropic Marin always pretty close to 1.0260 within a few .0001)
Temperature = 77 d F (InkBird set 77.0-77.5)
NO3 = 9.1 ppm (Hanna HR)
PO4 = 0.08 ppm (Hanna ULR)
Alk = 7.7 dKH (Hanna and Salifert actually match surprisingly)
Ca = 440 ppm (Salifert)
Mg = 1350 ppm (Salifert)
pH — never really check but pulled out old Red Sea and showed 8.2 but reference chart steps are just 8.0, 8.2, 8.4


I don’t dose alk/Ca as my few soft corals don’t seem to consume much if any between water changes.
*I do dose Trisodium Phosphate daily and have caused some swings but mostly maintaining 0.06-0.10 ppm

Nitrate and phosphate are typically good tracers, but you really don't know what your protein, carbohydrate,or amino levels are. Are you dosing any coral specific foods or Amino acids? Sorry if you've already hashed this out

 

[EricR]

Nitrate and phosphate are typically good tracers, but you really don't know what your protein, carbohydrate,or amino levels are. Are you dosing any coral specific foods or Amino acids? Sorry if you've already hashed this out

No idea about other levels, as you mentioned.
I was pretty convinced it was a flow change issue but hadn't considered the possibility of cleaner water,,, until now (based on a couple of the responses).
*definitely something to consider

I've never dosed any coral foods, aminos, etc.

Only "foods" going in are for the fish and inverts which then the corals get what they get.
I feed mainly LRS Reef Frenzy Nano with flake or dried phyto (soaked in Selcon) occasionally.

Willing to buy/try some coral foods if anyone has any suggestions (keeping in mind I only have a few zoas and a couple of ricordea).
Reef Roids, BRS Reef Chili, Red Sea AB+ ??? ...anything else sound good?

 

[EricR]

It could be the zoas are just temporarily getting used to the cleaner water. It may not directly relate to nitrate and phosphate levels over an extended period.
Lighting and PUR has a lot to do with the turbidity of the water and this could be affecting them too.
My zoas have looked like this for weeks on end before and opened just fine after fwiw.
I wouldnt be too worried but keep persistance afoot.

Excellent point about light through the (now) lack of turbulence there.

Tempted just buy a SUPER CHEAP little wavemaker to see if I can recreate turbulence that used to be over the zoas as an experiment.

Would probably be smart to move the HOB over to that (right) side to see what happens but a bit of a pain as I have a plastic trash bin for ATO stuffed in there that's not easy to move ... but doable as an afternoon/weekend project.

 

[MoshJosh]

You can make a flow diverter/diffuser. Basically a piece of plastic that angels the flow more upwards.

 

[Saltyreef]

Excellent point about light through the (now) lack of turbulence there.

Actually, its a little different definition vs turbulance.
Turbidity means opaque with sediment whereas turbulant is refering to the movement.

As sediment decreases in the water, the light refracts less and becomes stronger at a further depth.

 

[EricR]

Actually, its a little different definition vs turbulance.
Turbidity means opaque with sediment whereas turbulant is refering to the movement.

As sediment decreases in the water, the light refracts less and becomes stronger at a further depth.

I see. (Ignorance is bliss -- I'm going with the turbulence angle,,, just kidding)
Thanks...

Threw in a bag of ROX carbon out of desperation yesterday -- guess I should pull it out

 

[Saltyreef]

I see. (Ignorance is bliss -- I'm going with the turbulence angle,,, just kidding)
Thanks...

Threw in a bag of ROX carbon out of desperation yesterday -- guess I should pull it out

Take into consideration the timeframe you are doing all this in.

Has it all been over a month?
Or a week?

 

[EricR]

Take into consideration the timeframe you are doing all this in.

Has it all been over a month?
Or a week?

3 weeks ago (1/15) -- HOB change ... then went on vacation.
2 weeks ago -- back and noticed the calamity.
*so zoas have been closed for more than 2 weeks,,, just guessing probably closer to 3 weeks

1.5 weeks ago -- moved Nero to opposite (right) side -- had to since ricordea were getting blasted and sand getting moved/displaced.
Just in the last couple of days have I started trying to "mess" with things more.

...not sure if that's easy to follow but best recap I could come up with

 

[EricR]

Thank you all for all of the input,,, much appreciated.
Sorry for all the questions but since it’s almost the weekend, I want to decide if I should try anything or just leave them alone so, on that note…

How long can zoas stay completely closed before they start completely deteriorating?
*they’ve been closed for 3 weeks (or more) now so that seems way too long to me.
(Honestly don’t think I’ve seen all closed for even 2 days before in the 8-13 months I’ve had the different ones)

Any tips on judging acceptable flow around zoas?
I’m using 3”-4” strands of dental floss tied to a straw to just try to see what’s going on and the floss is barely staying horizontal, even sagging a bit.
*ricordea are getting stronger flow and I think that’s probably closer to what I’m shooting for but could be wrong — floss horizontal with some wiggle,,, ricordea skirts lifting a bit periodically.

I’ll also probably lower my lighting based on the “turbidity” discussion.

Not sure if I should try adding any type of coral nutrition, maybe liquid.
*I assume completely closed zoas won’t absorb any of it but, again, could be wrong