Seachem ParaGuard, 500 mL / 16.9 fl. oz. – 603
$18.99
Price: $18.99
(as of Oct 20, 2025 14:48:00 UTC – Details)
ParaGuard is the only fish and filter safe aldehyde based (10% by weight) parasite control product available. Unlike highly toxic and difficult to use formalin based medications, ParaGuard contains no formaldehyde or methanol and will not alter pH. ParaGuard employs a proprietary, synergistic blend of aldehydes, malachite green, and fish protective polymers that effectively and efficiently eradicates many ectoparasites on fish (e.g. ich, etc.) and external fungal/bacterial/viral lesions (e.g., fin rot). It is particularly useful in hospital and receiving tanks for new fish and whenever new fish are introduced to a community tank. For use in freshwater or marine. ParaGuard is recommended for the treatment of certain diseases in marine and freshwater fish only. It IS NOT recommended for treating any style aquarium containing invertebrates, corals, crustaceans, or elasmobranchs (sharks and rays).
Is Discontinued By Manufacturer : No
Product Dimensions : 2.44 x 2.44 x 7.62 inches; 1 Pounds
Item model number : 603
Department : Unisex-Adult
Date First Available : June 21, 2011
Manufacturer : Seachem Laboratories, Inc.
ASIN : B002DWTIU6
Best Sellers Rank: #16,556 in Pet Supplies (See Top 100 in Pet Supplies) #135 in Aquarium Water Treatments
Customer Reviews: 4.6 4.6 out of 5 stars 2,922 ratings var dpAcrHasRegisteredArcLinkClickAction; P.when(‘A’, ‘ready’).execute(function(A) { if (dpAcrHasRegisteredArcLinkClickAction !== true) { dpAcrHasRegisteredArcLinkClickAction = true; A.declarative( ‘acrLink-click-metrics’, ‘click’, { “allowLinkDefault”: true }, function (event) { if (window.ue) { ue.count(“acrLinkClickCount”, (ue.count(“acrLinkClickCount”) || 0) + 1); } } ); } }); P.when(‘A’, ‘cf’).execute(function(A) { A.declarative(‘acrStarsLink-click-metrics’, ‘click’, { “allowLinkDefault” : true }, function(event){ if(window.ue) { ue.count(“acrStarsLinkWithPopoverClickCount”, (ue.count(“acrStarsLinkWithPopoverClickCount”) || 0) + 1); } }); });
Bulk Pack Convenience: Includes three 500ml bottles for extended care.
Fish and Plant Safe: Ideal for use in both freshwater and marine aquariums.
Non-Invasive Treatment: Helps maintain aquarium balance without harsh chemicals.
Supports Aquatic Health: Assists in fostering a healthy environment for aquatic life.
Customers say
Customers find the water treatment effective at killing ich and helping sick fish recover, while appreciating its safety as it doesn’t harm plants or snails. The product receives positive feedback for its quality and stress-reducing properties, with customers noting their fish remain happy and healthy. While some customers consider it the best value for money, others find it expensive, and experiences with bacterial resistance and staining are mixed.
Otz –
I like it.
I use this all the time. I think it helps with their skin.
Jilla B𦠖
GREAT PRODUCT FOR GOLDFISH // UPDATE
I have a 17 year old goldfish and he’s never been sick at all. I’ve always only used a top quality water conditioner and he’s alone. A few weeks ago I noticed he was not himself…not eating and staying in the corner all the time with little perky swimming. I keep him in a very large, old fashioned bathtub with a big fountain for water // oxygen. I also notice a type of white stuff on him. First it was very pale white then became almost like a white salt look on him. I went into a major panic and bought this product. (along with a few other’s from Amazon for treating ich and other diseases)…. I moved him into a small tank with this medicine and completely cleaned out his pond and fountain. I added this to his fresh new pond/tub, along with water conditioner called Stress Coat (which I’ve used for all these years with no problems at all)……I have a soft / large net to gently pick him up to move him and he was so quiet. He’s usually a perky one….I got the net here on Amazon also. He’s at least 9 inches and looks ‘fat’ to me so I worried it could be bloating too. I put him back into his fresh tank / tub and waited a day before trying to feed to reduce anymore stress. YAY, he is eating again and swimming. He does enjoy my company though, lol…..I just love him. He’s bright orange and I don’t see any signs of disease again, yet. I did notice at times now he’ll spit out his fish food and go for tiny pieces of flake food on the bottom. That worries me a little bit so I’ve ordered new food for him too. I was very pleased with this product. Seemed safe and complete. It seems to have saved him and I am so grateful. I wish I knew what he’d enjoy eating so I can keep him happy and healthy. I hope he’ll be around for a long time. THANK YOU for this product. I used the Aquarium salt too but I think using this product primarily, did the trick as did cleaning out his tank // tub area completely too. It arrived on time. Amazon has saved my day more than once!! Any suggestions would be welcome to keep my fish glowing and going. Do I use it during EACH CHANGE? TIA~…………..UPDATE:::: 12/18/2013 – Ohh no – My fish has that stuff on him again and he’s not acting right. I bought him blood worms and new fish food of pellets (I have always only fed flake food) and he won’t eat any of it now. He’s not his perky self. He knows when I come in and swims over to me…is breaking my heart. I took pics of him but not sure if anyone can view them that knows goldfish. He seems ‘off’….and a tiny // slight tilt. He does not fight me when I reach down to pass my hand over his side to remove those white thingys (like salt)). I don’t like touching him as I may injure him more. IS THERE ANYONE TO ASSIST ME IN HERE? He has never been sick 1 single day in his life until we had to move to this horrid place. : (( – Should I attempt to move him outside as I have a big pond thingy out there for him but worry about wild animals then. I also bought Pimafix from Amazon but not sure if I can add it to his water too. It treats fungal infections. I just don’t know the answer and don’t want to make things more toxic. Thank you.>>>>>>>>>>>>>UPDATE Dec. 28, 2013 – ALL IS GOOD : ))) Ich is gone again and I keep re treating. This is a great product // Thank you and Elvee thanks you. You MUST re treat as this disease has cycles per my Marine Vet.********UPDATE January 9, 2014 – This did NOT cure the Ich – per my mobile fish vet today she told me to buy this from Amazon, which I did::::Mardel Quick-Cure Aquarium Treatment, 4-Ounce…………..I did not know they “sedate” a goldfish to examine them…. I could not watch.. my vet is great and I purchased the new Ich medicine above, more oxygen piping, etc. My fish vet sedates my Elvee, in a separate bucket and it is Ich. Also my water was not right so I had to buy a API water test kit here on Amazon. You can never oxygenate too much. She said my Elvee is happy and spoiled tho… : ))…….
Sara D –
Used successfully to treat scutariella
I used Seachem Paraguard to treat scutariella on yellow shrimp in my 10 gallon. I know that this product has not been tested (per Seachem website) with invertebrates but I had tremendous success! Background on the tank: 10 gallon, inhabited for six months, 12 espei rasbora, 7 asian moth catfish, 1 ghost shrimp, 5 amano shrimp and 25-30 yellow neocaridina shrimp of various ages and stages (juveniles, adults, berried females and some teensy newborns). I removed the carbon from the filter and dosed everyday for two weeks. Water changes stayed current (1-2 x per week of 15-20%). Not all of the yellow shrimp had scutariella, I counted roughly 6 but those six visibly had signs on their rostrums and heads. Within the first couple of days of treatment, I saw immediate improvement. After a week, I only had three shrimps that showed scutariella and I pulled those out and did a salt dip (1 tb. salt to 1 c. tank water – soak for 30-60 seconds, the parasite falls off immediately). I continued to medicate the tank for a few more days to ensure that I did not see anymore signs of illness. The combination of Paraguard and salt dips worked wonderfully! I have a heavily planted tank and it would be difficult to use the salt dip for everyone. I did not lose any shrimp or fish and I see many juveniles and newborns) and nobody showed any signs of stress. I have over half of a bottle left which I will keep on hand for other issues that may arise. A wonderful product! It is a blue/green color but does not turn the tank water any colors and is quickly dispersed. Also, if you are treating shrimp for scutellaria, be sure to remove molts as the parasite stays in the molt. The medication is only active for 24 hours, so I suggest doing water changes before adding medication to ensure that it remains in the water for therapeutic purposes. I kept an easy routine of dosing in the morning, on water change days I changed the water and then added medication.
Emanon –
Good stuff!!
Super reliable product. I’ve been using it faithfully for years.
Rall Mekin –
All of them had horrible levels of ammonia and one also had toxic nitrite …
WARNING: IT WILL KILL YOUR NITRIFYING BACTERIA BED.Product advertises that it will not negatively affect your bacteria bed. At first, it doesn’t seem to. Yet in 3 out of 5 cycled tanks I used it on, my bacteria bed suddenly seemed to die off.My husband and I maintain about 14 fishtanks. Many of them were newer but they had been cycles for weeks and I considered one of them somewhat established.In two of our quarantine tanks and a 48 gallon show tank, I decided to treat for fill flukes because in one tank, it seemed I had a nasty case break out. I had been so impressed with stress guard recently, I decided to try Paraguard to treat both flukes and any other parasites on our new goldies.One tank received treatment for 7-8 days before we left on a weekend trip to see our niece graduate. The others had 1-4 treatments. The day after I returned I noticed that some of my fish looked badly stressed. All of them had horrible levels of ammonia and one also had toxic nitrite levels.This resulted into being up to midnight two nights in a row doing water changes and shuffling fish around. It was two nights in a row because I did not realize one tank was having problems until I saw my Tosakin gasping for breath and looking VERY unhappy in his well established coffee top table show tank.That said, I know I had several fish that had symptoms of gill flukes. This medication seems to have eradicated the infection in them. I used baths initially, and I highly suggest bathing all incoming fish in a mixture of this as directed before putting them in primary tanks.I give it 4 stars because it works really really well. I have to take off a star because of the headache of a product that says it will not harm the bacteria bed, though is absolutely does so.
Michael –
Amazing medicine to always have on hand for sick fish
Ravi J –
Great product!!
Raphael Fernandes –
Good product. One of the few products that can be safely used on invertebrates.I used this product for a whole month by dosing my tank daily. I lost just one Cardinal Tetra and a little harm to my aquatic plants. But all good.Would go for it again.
Lionel Locksley –
Quick delivery and good quality as expected.
Sanjay –
all my fish die