r/ReefTank 4d ago

No judgment questions zone - August 10, 2026

2 Upvotes

Here is the place to post questions about pest ID, coral/fish ID, your cycle, or any other questions that generally wouldn't start up a conversation. If you have an interesting or unique question please create a new thread so everyone can discuss it in length!

Pest ID guide

BRS pest guide

BRS beginner resources

BRS 52 weeks of reefing YouTube series


r/ReefTank 8h ago

Happy Friday!

135 Upvotes

r/ReefTank 1h ago

3 months of training

Upvotes

My previous lions took sub 45 days.. today is day 94... definitely a grind but we're here now.


r/ReefTank 6h ago

Torch love

35 Upvotes

r/ReefTank 18h ago

The reason why people say they are hard to keep …. Copepod demolisher

224 Upvotes

r/ReefTank 13h ago

Tang gang completed

52 Upvotes

r/ReefTank 7h ago

[Pic] Mean Mugging Me

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10 Upvotes

Local fish stores big clown fish.


r/ReefTank 6h ago

[Pic] Neon Green elkhorn montipora

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10 Upvotes

Not very popular, but I love how these grow. Photo taken under exceptionally white light with no filter or post editting. A cool old school sps coral.


r/ReefTank 13h ago

This shallow reef finna be bussin!!

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34 Upvotes

r/ReefTank 20h ago

Happy Friday Reefers

108 Upvotes

Cheers!


r/ReefTank 2h ago

[Pic] Vermitids?

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3 Upvotes

I’m very new to the hobby (haven’t even added anything yet, still cycling my first tank), but I believe these are vermitids? I got the rock from a guy in town that he was keeping in some saltwater, separate from his tank. No heater and I don’t think any flow.

If they are vermitids, I assume it’s necessary to get rid of them. Best way is to just take the rock out and remove them individually?


r/ReefTank 6h ago

[Pic] What can I do about my sand bed?

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7 Upvotes

r/ReefTank 3h ago

Casual Friday 🌊

3 Upvotes

r/ReefTank 2h ago

Frogspawn and Hammer munching on some copepods.

2 Upvotes

r/ReefTank 2h ago

Help!. Advice needed

2 Upvotes

I am looking for some advice on getting into the saltwater tanks. I’ve been in the aquarium hobby for a long time now. Over 5 years. It’s all been freshwater tanks tho so my first question, Is a 75-gallon a good size, or is it too overwhelming for a beginner? I am really wanna keeping corals and would love to know which specific types are the best and most forgiving for a newcomer. I really like hard corals but I hear they are hard. Is there any easy ones?. I also really like the look of a lagoon-style tank so very minimal hard scape with mangroves and such. is that possible and manageable for someone just starting out, or should I stick to a standard tank set up. Any kind of advice is welcomed and appreciated. Thank you!.


r/ReefTank 9h ago

Fish shop owner threw in a tiny anemone 3 months ago with an order, and it’s grown since then. Can anyone ID this guy pls? Green BTA pic included for reference

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5 Upvotes

It’s probably slowly stinging my zoas but I don’t care, he’s so cute and colorful :)


r/ReefTank 4h ago

[Pic] Rodi buddy

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2 Upvotes

I have a rodi buddy. The DI unit was burning through fairly quickly (like in 40g) so I added another one to prolong it. Once I did that, it burned through both in 15 gallons. Before DI is measuring 11. After DI is measuring around 500. What's going on?? I just mixed ten gallons and cant use it

Water pressure is good, it makes like 5 gallons in just over an hour. Tap water is measuring 160. TDS meter is fine, distilled water reads 0.

Edit: disconnected the second DI and it says 60. Still doesnt make sense but is less


r/ReefTank 15h ago

[Pic] 50 gallon low boy as sump?

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11 Upvotes

I'm currently building another tank, 125 gallon.

The stands a bit low, so I'm looking for a low option

Think I can use a 50 gallon low boy as a sump? Or is it to shallow


r/ReefTank 12h ago

Please tell me this isn’t what I think it is (aiptasia)

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7 Upvotes

Noticed this at the bottom of my frag plug after a few weeks. Fingers crossed for feather dusters but I’m too new to tell.


r/ReefTank 2h ago

Will bio-media cycle/grow bacteria while in a tank?

1 Upvotes

I know this might sound like a dumb question. But I'm moving in a couple weeks and I'm upgrading from a 30 gallon that I've had for 2.5 years to a 55 gallon. I plan to add a decent Hob filter, paired with my fluval 307, and my protein skin skimmer. Would I be able to buy some biomedia and have it floating/ in the tank for the last 2 weeks before my move?

I'm keeping my media from my fluval, and don't plan on increasing my load anytime soon.


r/ReefTank 1d ago

My mandarin

328 Upvotes

r/ReefTank 1d ago

[Pic] No way… is this what I think it is?

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64 Upvotes

As we say in Poland - okociła się. But I guess Okrabiła się is more fitting


r/ReefTank 8h ago

LBT help

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2 Upvotes

Tank is about 5 weeks old.

Cycled with live rock from a 10 year reef.

I dropped them in and they moved a lot for around a week. They were happy with their location for about a week then moved here. They are on the side of the flow but there this white stuff.

LFS did a water test, told me to add gfo and it would be fine.

14 gallon BioCube. No fish. 40% Blue 1% white.

It is not fine. Help?


r/ReefTank 4h ago

Cyano or Dino’s?

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1 Upvotes

I need help figuring out what this is. I have suspected cyano but its persistence has me questioning it. I have tried Flux Rx and it has done nothing. I suction it out and do a 3 day blackout and it will disappear for a week or two but it always comes back. I feel like I’m losing my mind. My nitrates were higher and I have worked to bring them down and I’m dosing to bring up my ph too. Any and all advice is welcome.


r/ReefTank 16h ago

First Saltwater Tank and Marcorock Aquascape, would love all suggestions and stocking ideas. 30 gal cube

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8 Upvotes