Am i over crowding?

[mattyb]

Hey guys

i think i might be overcrowding my fish tank :s or do i need another filter? high nitrate levels

i do a 30% water change every week, i have not checked the nitrates in 2 weeks, i did a test and was at 120ppm (highest level my test does, might be higher) nitrates when i only did a water change 4 days ago! after getting that reading i did another water change, did about 40%, left over night, checked the nitrates this morning and is at 30ppm which is still a little high. Do i have to much fish? im going to do another water change today and see how it goes later on.

i checked my testing kit with straight tap water just to make sure it is all ok, tap water measured at 0ppm so the kit is all ok

300L fish tank (80G)
Planted tank
Ph - 7.4
Amonia - 0.25
nitrites - 0

Fish:
9 discus (2 at 4.5 inches, 5 at 5 - 5.5 inches, 2 at 6 - 6.5 inches)
24 neon tetras
4 cae's
6 bristlenoses (1 - 2 inches)
4 clown loaches (2 - 2.5 inches)

feeding is good, 3 blocks of frozen food in morning, 4 blocks at night, dont last more than 10 mins with food (range of blood worms, discus dinner and beefheart)

every water change clean about 60% of gravel in tank that is not planted (middle of tank where i drop the food)


Any advice will be really great thank you

[discuspaul]

Yes, I would say your bio-load is somewhat high. In that circumstance, you're not doing sufficient wcs - you should be aiming for at least 3 X a week of 50%-70% or more - you need to bring those nitrates down to less than 10 ppm on a consistent basis.

[Nu2Discus]

Wow that seems like a LOT of fish in an 80 gallon tank. But your real answer is in your parameter values.

[Ryan]

Most biological filtration will not remove nitrates -- they are actually creating it. You can buy products that absorb nitrates, add plants, etc. to try and get it under control, but the simplest and most effective way to remove nitrates is with water changes. To get it into check, you need to start 50% daily water changes until the readings are 10ppm or below. Keep in mind that dirty filter media, dirty substrate, etc. can contribute to high nitrates if there is a lot of waste and uneaten food trapped in them. My first suggestion to people with high nitrates despite water changes is to clean their filters and sand/gravel. In your case, though, the amount of water changes you're doing are low in comparison to the stocking density of your tank.

[tonytheboss1]

Amonia - 0.25 ???
nitrites - 0

:bandana: It appears your cycle is a bit off besides your super high nitrate level. Your Ammonia should be '0'.


Fish:
9 discus (2 at 4.5 inches, 5 at 5 - 5.5 inches, 2 at 6 - 6.5 inches)
24 neon tetras
4 cae's
6 bristlenoses (1 - 2 inches)
4 clown loaches (2 - 2.5 inches)

Mega bio-load for only 80g of water. Short term - Increase W/C's to 75/90% daily till you lower your nitrates to at least 10ppm.
Long term - You need a larger tank or a lot less fish.

[mattyb]

So looks like to much fish for my tank, I have a 420L (110G) sitting outside but that is a few months away as building a new stand/cabnet for it. Is that big enough or should I sell that once finished build and go for a 1000L (264G) tank?

[tonytheboss1]

:bandana: 110g is definitely a step in the right direction. 9 adult Discus could be quite comfortable space wise & you wouldn't have to kill yourself with W/C's to keep nitrates in chk. If you want to house all your guys in one tank then the 1000L sounds about right.
I'll give you an example. In my 120g w/ [30/40] various Tetras, GBR's, [2] Raphael Cats & [8] Discus adults I change about 75% every 4 days to maintain around 5ppm nitrates consistently. Now I'm sure it could be stretched a bit further but this works for me. Your W/C regimen will be determined by how quickly that bio-load sends those nitrates above 10ppm. "T"