Ok, I finally have to ask about this. I have had my 30 gallon for 20 years and my 10 gallon for about 7. I love platys and am always hearing how they are an easy fish. I have NEVER had a platy or a sword last more than a month. My tanks are cycled, no ammonia, no nitrite. My ph is quite high, 8.0-8.2, but I've given up trying to regulate it. I have about a half a teaspoon of salt per gallon in each tank, although I just started the salt about ten years ago and the platys die regardless of salt.

I have had tetras of various kinds, all sorts of barbs, loaches, mollies, angelfish, a black ghost knife, a bala shark, and various other freshwater fish you find at the pet store. All breeds lived long and happy lives. Gouramis don't seem to like either tank, but I can live without them.

I want platys in all their many colors very much, but it just does not work. I get them, they are OK for a couple days, then they get lethargic and die. The only platy this didn't happen to was the most beautiful fish I ever had, orange and black, lyretail, stark raving crazy, committed suicide by jumping out of the lid opening in the back of the tank. Is it the ph? Every other breed besides the gouramis does fine.

A few simple observations.
First observation: Most of the fish that are thriving in your tanks like water that is very low in mineral content. That is simply not true for platies. Have you checked your GH or TDS to see where the water mineral content stands? Although high pH water is often high in mineral content, it is not a certainty. Salt is not needed in any tank except a saltwater or brackish tank, and in those you want a sea salt mix, not table salt or "aquarium salt".
Second observation: The fish that you are doing so well with like a diet high in animal protein and will do very well on mostly all live or frozen foods. Platies need a fair bit of vegetable matter in their diet and will do better with things like spirulina flake food than with high protein food.
Many of the fish that have done well for you like warm water, close to 80F. A swordtail will do better at 75F and is near its upper tolerance limit at 79 to 80F.

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Fishless cycling

Thanks. No, I have not checked my mineral content. I have my suspicion that it is quite high, judging by the rock that forms where ever our water lands, but I don't know that for a fact.

The food is a good idea. I have bought vegetable flake food in the past, but I never seem to stick to it, not wanting to short the protein eaters. I guess I need to try again and train myself to mix the food more reliably. My tank temperatures were kept around 75 for a long time. Until I got the angels and realized that they preferred a bit higher.

As for salt....I know it is controversial, but I have had markedly better luck with fish life span since I started adding it, so I maintain it.

Thanks for your thoughts.

Robin, try kensfish.com

they are 10x cheaper for 10x more food and have them in 1/2 pound bags. I have a variety in the same tank and was shorting the vegans of the tank, got what I needed for the types of food the fish truly need and mixed em when I got them. for under 10 bucks you can have a pound of different flake instead of 10 bucks for a few ounces.


My angels spawn when the water is at or around 75. and I am there with you on the salt.

I keep my Platy in strictly freshwater and they do perfect, food for tropical fish mixed with livebearer food and a few algae wafer bits every now and then, 20+ fish, temps 83F, 55g, tons of plants.
Maybe it's something to do with the change from freshwater from the store to salt in your tank. I only clean the sand maybe once a month, no need to do it any sooner.
I have dreadful luck with Guppies & Molly fish tend to get an unusual/unknown illness several months later and pass no matter what I do.

i have 5 platys in my 38g, 3 of which i have had since they were fry. my pH IS 7.2-7.4-ish tank stays at 76-77 degrees. the 2 males i have have only been here 2 or 3 weeks. the other 3 females have been here 3 or 4 months. i dont really do much for them..the tank kinda runs itself.....i check ph regularly and nitrites regularly...everything stays in check...im new to this and dont know much but of all the fish i have had in the past 9-10 months the platy's have the most successful. i had alot of cycle issues but im sure you dont have that since you have had the tank for so long. what are you using ot test your water with? im sure you know but just in case..those test strips are worthless. just figured i would ask becuase if you are using test strips your problem may be right there in front of you.

Yeah, I used to use those test strips, but for my new 20 gallon, I bought the API Master Test Kit for it. I LOVE it. Very accurate, easy to use. Makes your water checking like a mini chem lab

Thanks for the info on food. I will take a look.

hey!
i have had platties for about a year and they are very hardy for me. i keep them at a temp. of about 75-80 and a pH about 6.5. i have had no problems with the fish except for clouding and i don't do that much maitnece. so i would say if you want to change your pH you can try to use distilled water. i tried those chemical things and they would bring down the pH down for like 3 hours and then it would go back up. so what i recomend is using distilled water. it has a naturally low pH around 7 but i think the one that i buy is lower. but all i do is treat it and mix it in with the tap water untill it is balanced out at the right pH. it works wonders and you just have to add a little more in every time you do a water change. hope this helps!

I have no problem with Platies and I use aquarium salt. I have subjected them to 3 times the recommended amount for periods of time and still they go on. My tap ph is 8.2 and although I now mix 50/50 RO that brings it down a little, when it was higher they still had no problem.

I would ask if you are acclimating the fish to your tank before you put them in there?