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Description
Diamond Trigger Fish Rhinecanthus RectangulusDiamond Trigger Rhinecanthus rectangulusOverview: The Diamond Trigger is a small, colorful marine fish renowned for its distinctive diamond shaped patterns and bright blue, yellow, and orange markings. Its compact size and active swimming behavior make it a lively and visually appealing addition to reef aquariums. Origin: Native to the Indo Pacific, commonly found on shallow coral reefs and lagoons from East Africa to the central Pacific. Feeding:
Diamond Trigger – Rhinecanthus rectangulusOverview:
The Diamond Trigger is a small, colorful marine fish renowned for its distinctive diamond-shaped patterns and bright blue, yellow, and orange markings. Its compact size and active swimming behavior make it a lively and visually appealing addition to reef aquariums.
Origin:
Native to the Indo-Pacific, commonly found on shallow coral reefs and lagoons from East Africa to the central Pacific.
Feeding:
Omnivorous – enjoys a varied diet of meaty foods such as shrimp, small fish, crustaceans, and marine pellets, supplemented with occasional algae-based foods to support health and coloration.
Tank Mates:
Suitable with peaceful to moderately semi-aggressive tank mates. Avoid very small or delicate species, as the Diamond Trigger can display territorial behavior.
Aggression:
Moderately territorial – generally peaceful in larger tanks but will defend its space in smaller aquariums.
Experience Level:
Intermediate aquarists – thrives in a mature, stable reef aquarium with good water quality and adequate hiding spots.
Water Parameters:
- Temperature: 74–79°F (23–26°C)
- pH: 8.1–8.4
- Salinity: 1.020–1.025
- Minimum Tank Size: 75+ gallons
The Diamond Trigger is a vibrant, manageable triggerfish, perfect for reef or mixed-species setups where a colorful, active species is desired.
Shipping Notes
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Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
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4.7 ★★★★★
Based on 1932 reviews
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Product Reviews
★★★★★ 4
Good office chair for the money
Color: White
It is a good quality chair that is comfortable and aesthetically pleasing.
The arms aren't necessarily big enough to hold our cat - but that's because he's fairly large by cat standards. The arm rests moving is definitely nice and provides lots of opportunities to 'setup the chair' in a way that works best for you.
The instructions were relatively easy to follow (take your time and think it through to make sure you have everything 'aligned right' at first) and the chair is sturdy and holding up well.
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Reviewed in the United States on April 17, 2026
★★★★★ 5
Comfortable. Great Value for money. Easy to assemble. Great customer service.
Color: Black, Size: Pack of 1, Color: Black, Size: Pack of 1
I've been looking for a new chair to replace a cheap $30 chair i bought off of Amazon last year that had been killing my back and shoulders. I wanted something in the $150-$200 range and settled on the M18. Shipping was a fast 3 days with Prime and the box arrived in great condition.
All parts were separately wrapped or in their own boxes. Came with all hardware and nothing was missing. Assembly took me a little longer then normal because i have rotator cuff injury in my left shoulder so that arm is mostly useless. The most difficult part for me was attaching the wheels to the base. Other then that it was simple.
Once the chair was assembled i sat in it for the first time and started making my adjustments with the recline feature, armrest level along with the headrest. Next i reached around for the lumbar support knob and tried to adjust it but with my bad shoulder i decided to just get out of the seat and turn it around and adjust it with both hands. After spinning the chair a round to get at the lumbar knob i noticed a large crack in the plastic in the middle of the back of the lumbar plastic piece. I had not made any lumbar adjustments yet so i assumed this is how i received it. The lumbar support comes preinstalled to the backrest so it either was damaged before or during the shipping process. Either way it was damaged before being delivered to me. The lumbar support still functioned properly but it was still broken.
I decided to contact Sihoo's customer support that came along with the installation instructions regarding the damaged lumbar piece. I received a reply the next day and after sending them some more info about my order and a couple pics they shipped me a replacement part which took a week to arrive. I swapped out the damaged part and after owning the chair for a week so far i am really happy with my purchase.
Im about 5'10 180lbs. At its highest height level my feet reach the ground comfortably flat footed. The backrest fully covers my back and the headrest adjusts very well to sit on the back of my lower head/upper neck. The armrests only go up and down....not forward and back or tilt inwards. This is fine for me as they are grooved to fit your forearm while sitting at your desk/keyboard. The armrests are also a soft cushioned rubber material...not a hard plastic. The mesh of the backrest and headrest are good material and seem well made. The seat is very wide and the cushioning is firm which i prefer. Usually more firm cushioning seems to last longer and hold its form. The base of the chair is VERY sturdy and made of all metal. My chair is on carpet and holds its position very well. As far as recline goes you can set it to recline all the way back, half way or lock the chair in the upright position. You can also adjust the resistance on the reclining feature.
So that being said im very happy with my purchase. It arrived with a slight flaw which the company corrected in a fast manor and was very polite in their customer support. I personally don't have a lot of experience with many office chairs and have never used a high end chair($500-$1000+) chair before to make any comparisons. All my chairs for the most part have been from local stores like Staples or Office Depot. Id recommend this over anything they carry in this price range....and i went and looked at their products before buying this chair as well.
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Reviewed in the United States on September 1, 2023
★★★★★ 5
SIHOO M18 chair is amazing
Color: Black, Size: Pack of 1
I purchased the SIHOO M18 Ergonomic Chair a few years ago and have really enjoyed it. It’s very comfortable and offers multiple adjustments, whether you want to recline and relax or sit upright for work. The back support is also excellent, and I haven’t had any issues with the chair at all. You can easily tell it’s high quality from the build and appearance—no creaks or noises whatsoever. I highly recommend this chair to anyone in the market for a new office chair.
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Reviewed in the United States on June 12, 2026
★★★★★ 4
Good budget-friendly option
Color: Black, Size: Pack of 1, Color: Black, Size: Pack of 1
The chair arrived 4 days early and was easy to put together by following the instructions carefully. It feels sturdy and comfortable. It does support the lumbar region of the back and the arm rests are adjustable vertically as well as the head rest. I wish the arm rests were able to rotate in and out for added customization and that the back of the chair could be adjusted up and down for more precise support. But for a budget chair, it does a good job.
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Reviewed in the United States on June 4, 2026
★★★★★ 5
A solid chair for the budget conscious sitter.
Color: Black, Size: Pack of 1
While this is not THE most comfortable chair, let's face it - if you sit for long periods, what chair IS? I bought this chair because I'm making a career change. I've returned to school and spend hours at my desk. At the age of 50, sitting for a long time with my nose pointed toward a book can be hard on the seat, back and neck. I looked at all kinds of office chairs and settled on this one, primarily because it was on sale, was in my budget and so I clicked the "Add to cart" button and hoped for the best.
It was delivered, and I had to work that evening, and when I got home my 17-year-old son had assembled it. My theory on the simplicity of assembly can be deduced from that sentence above. He didn't have any extra parts left over and the chair was complete!
I sat down. I leaned back. I shifted the lever that keeps the chair in an upright position and sat straight up.
Okay! I can live with this. It has been almost two full months of using this chair and I have no problems.
Pros:
easy to assemble
sufficient comfort level - adequate cushion in the seat
can be leaned back or pop the lever in to stay straight up
rollers on bottom
headrest is adjustable
affordable
easy to clean
arm-rests can be moved up or down
height adjustment is self-explanatory - you'll figure it out
the "lumbar" support is actually comfortable - it's "there" if you back up to it but if you scoot forward just a bit, you won't feel it if you don't want to sit like that
Overall this seems like a chair that's going to last me for a few years, at least, and not fall apart. In the context of size, I'm not a small or extra larger person. I'm an average middle-aged woman with meat on the bones. The seat is plenty big enough.
I would recommend this chair as an upgrade to the hand-me-down office chair that just isn't comfortable any longer.
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Reviewed in the United States on April 1, 2023