fish dying

[erikbb]

Hello, I think I need some help and I am a beginner. The tank started around last June. Now, over the course of the last month or so I have had a few fish die. I have a tank full of glofish: danios, tiger barbs, and tetras (approximately over 30 glowfish). The tank used to have a pleco. The tank has 2 snails. The tank was glofish ornaments only but I switched to try a planted tank, so now the tank has 1 ornament and 6 different kinds of plants with glofish gravel. Now it has nematodes from excess waste or introduction of plants.

The first fish to die was a pleco, then I got another one and he died. (About this time I started using seachem flourish root tabs and about a month after I started using seachem excel for the plants.) After those 2 have died the glofish are slowly dying, one green tiger barb, two red tiger barbs, 1 small danio. I would say there is about a week apart from when each fish dies. I think another green tiger barb is about to die, he has a sunken in belly.

Should I stop the seacheam excel? Also my nitrates are usually high at 40 ppm or higher, I can never bring it down. Ammonia and nitrites are always low.

Any tips or advise?

 

[agrasyuk]

40ppm is very very high, it will not kill fish instantly like Amm but it accumulates over time. more frequent /larger water changes are always a solution to get rid of nitrates.
you never mentioned the size of your tank, 30 fish is significant load even for a 55gal.

 

[coralbandit]

What is your maintenance schedule. Many experienced plant people who use ferts do 50% a week water changes..Nitrates are easily reduced with water changes..
The % of water you remove is the % the nitrate, ammonia and nitrites will be reduced.
40ppm and a 75% water change will leave you with 10ppm unless nitates are in your source water.
Match temp closely and dechlorinate.

 

[erikbb]

Oh yes, sorry the tank is 20 gallons. How can I heat up the bottles of RO water I use to match closely match the temp of the water? They are small liter or gallon bottles.

 

[agrasyuk]

Fish experience temperature swings in nature, pouring room temperature bottles would not be a problem. If you really insist to preheat then pour the water into a tub, throw a heater in till you happy. To much work if you ask me.

But regardless, at the moment water temperature should be the least of your worries. In a 20 gallon I would not keep more then 10-14 tetras

 

[erikbb]

Thanks everybody, I will do water changes more often? I usually do it about once a week.

 

[coralbandit]

RO water alone is not needed in almost all cases.
I mix my tap that has a TDS of 350 + with RO to get 'soft' water [under 100 TDS] for my rams..Pure ro is lacking the minerals many fish require in the water..
Topping off with RO is fine and will help to keep your TDS from accumulating to much higher levels.
TDS meters are about $20...
This one does TDS and Temp...It is what I use .
https://www.amazon.com/HM-DIGITAL-T...=UTF8&qid=1515181729&sr=8-2&keywords=hm+tds+3